There's a widely repeated piece of advice that getting a second dog will fix a first dog's separation anxiety — the logic being that two dogs can keep each other company while the owner's out. It's intuitive, well-meaning, and, according to the research that's actually looked at it, often backwards. A study that filmed dogs left alone in single-dog and multi-dog households found that dogs in multi-dog homes barked and vocalised more, not less, particularly in the first hour after the owner left — and the researchers concluded they couldn't support the idea that having a canine companion helps a dog cope with being left. In practice, adding a second pet doesn't remove separation anxiety from the house. It often just adds a second axis the anxiety can run along — anxiety about the owner leaving, and anxiety about being apart from the other pet, which can show up on its own even when the owner is right there.
This guide is about that second, less-discussed problem: pets who are genuinely distressed by separation from each other, not just from you, and what actually helps when a multi-pet household has this particular knot to untangle. If what you're dealing with is more straightforwardly about a single pet struggling when you leave the house, our piece on why some dogs hate being left alone covers that mechanism in depth and is worth reading alongside this one, since the two problems often overlap in a multi-pet home. The Big Den Pro is a good starting point for either problem — a proper, enclosed den space genuinely helps build the kind of independent confidence this guide is largely about.
Why a second pet can make separation anxiety worse, not better
The appeal of "get them a friend" makes intuitive sense because loneliness looks like a plausible explanation for a dog's distress when left alone. But true separation anxiety isn't simple loneliness — it's a specific panic response tied to the absence of a particular attachment figure, and for many dogs that figure is the owner specifically, not "a companion" in the abstract. Adding a second dog doesn't change the underlying attachment; it just adds a second relationship into the house, and that relationship can itself become anxious and dependent if it isn't actively managed. The research bears this out: multi-dog households showed more vocalising when left, not less, especially in that first hour of highest stress — which is exactly when a true separation response peaks, companion or no companion.
Where a second pet can genuinely help is with boredom and general under-stimulation, which is a real but different problem from separation anxiety — a bored dog benefits from company and enrichment, while a dog with genuine separation anxiety is responding to the absence of a specific attachment figure in a way that another pet in the room often doesn't resolve. Telling the two apart matters, because the fixes are different: boredom responds well to enrichment and a companion; genuine separation anxiety needs a structured desensitisation approach regardless of how many other pets are in the house.
Littermate syndrome: when two young dogs bond too tightly, too early
This is the clearest, best-documented version of pet-to-pet separation anxiety, and it's worth naming specifically because it's so common and so preventable. When two puppies — true littermates or simply two puppies of a similar age — are raised together from early on, they can bond to each other more strongly than either bonds to their owner, especially if they're rarely separated and rarely trained individually. The result, often called littermate syndrome, isn't a formally recognised medical condition, but it's a well-recognised behavioural pattern: codependence and genuine distress when separated, fear of unfamiliar people, dogs or situations that the pair hasn't faced together, and sometimes reactivity or outright aggression toward new dogs or people, on top of the practical problem that each dog's individual training lags because attention has been split between two puppies instead of focused on one.
The single most effective prevention is simply not getting two puppies at the same time in the first place, but that's not useful advice if you're already past that point. For households already raising two young, closely bonded dogs, the fix is deliberate, structured separation built into daily life from early on — not punitive, just routine — covered in detail below.
Recognising pet-to-pet separation anxiety versus ordinary bonding
Close bonds between pets in the same household are completely normal and not something to actively discourage — dogs who enjoy each other's company, cats who groom and sleep curled up together, a cat and dog who've become genuinely attached, are all healthy, happy outcomes of multi-pet life. The distinction that actually matters is between closeness and panic. Ordinary bonding looks like two pets choosing to be near each other, settling calmly when they are together, and coping reasonably — if not enthusiastically — when they're briefly apart. Problematic over-bonding looks like genuine panic on separation: frantic pacing, excessive vocalising (howling, whining, persistent barking or meowing), scratching at doors or crates trying to reach the other pet, loss of appetite when apart, or physical signs of stress like excessive drooling or shaking that specifically appear only when the two pets are separated and resolve once they're reunited.
A useful practical test: separate the two pets briefly, in a calm, low-stakes way — different rooms with doors closed, for ten or fifteen minutes during an ordinary day — and watch what happens. Settling within a few minutes, perhaps after an initial bit of unsettled pacing or a few calls, is a normal adjustment. Genuine, escalating distress that doesn't settle, or that ramps up the longer the separation continues, points toward the kind of over-bonding this guide is addressing.
Building independence without breaking a healthy bond
The goal here isn't to make two pets dislike each other or spend less time together generally — it's to make sure each one is genuinely okay on their own, so that a bond is a source of comfort rather than a source of panic the moment it's interrupted. The most effective approach across dogs is deliberately scheduled, brief separations built into the ordinary rhythm of the week, rather than only being separated in emergencies like a vet visit, when the stakes and the stress are both already high.
Separate sleeping arrangements are one of the simplest versions of this. Two dogs who've always shared a bed or a crate have had zero practice coping without each other at the exact time of day — settling down to rest — when that skill matters most. Moving to individual beds or crates in the same room initially, then gradually to separate rooms if that's workable for the household, gives each dog nightly practice at being calm without their housemate inches away. The Big Den Pro works well for this specifically because a proper enclosed den gives a dog their own defined, secure space rather than an open bed that still feels like shared territory — and a den that's genuinely theirs, associated only with calm and safety, builds the kind of independent confidence that a shared sleeping spot doesn't.
Separate walks and separate training: time apart that doesn't feel like punishment
Walking two dogs separately, even if only once or twice a week rather than every outing, gives each dog their own experiences, their own one-on-one time with their owner, and crucially, direct practice being away from their housemate in a context that's genuinely enjoyable rather than stressful. This matters more than it sounds — a dog who only ever experiences the world alongside their companion has had almost no opportunity to build confidence that functions independently of that companion being present.
The same logic applies to training. Even five or ten minutes of individual, focused training per dog — a few basic commands, a trick, simple engagement exercises — does double duty: it builds each dog's individual confidence and skills, and it's itself a structured period of calm separation that reinforces the lesson that time apart is fine, even good. Training one dog while the other rests calmly in their own den or bed elsewhere in the house, rather than both dogs underfoot during every session, is a small, repeatable practice that compounds over weeks into genuinely more independent pets.
Cats and dogs bonded to each other: a slightly different picture
Cross-species bonds — a cat and dog who've become genuinely attached, or two cats who groom and sleep together constantly — follow broadly the same principles but with a few cat-specific wrinkles worth knowing. Cats are generally less prone to the dramatic, vocal distress dogs show on separation, which can mean a genuinely anxious cat gets missed simply because they're quieter about it — watch for subtler signs instead: a cat who stops eating, grooms excessively, or hides for an unusually long time specifically when their companion is removed from the house (a vet visit, a groomer appointment, boarding) rather than when the owner alone is out.
Giving each cat, or the cat in a cat-dog pairing, their own elevated resting spot, their own hiding and retreat option, and their own feeding station reduces the degree to which they're relying entirely on the other pet for a sense of security in the home. The Big Burrow Donut Tunnel Bed and a Big Lookout Window Hammock positioned in a different part of the house from a dog's usual resting spot give a cat a genuinely independent retreat that doesn't depend on proximity to a canine housemate, which is a meaningful step toward the same kind of standalone confidence the training and walking advice above builds in dogs.
Introducing a new pet without creating the next over-bonded pair
If you're planning to add a new pet to a household that already has one, there's a genuine opportunity to prevent over-bonding before it starts, rather than untangling it later. Deliberately building some individual time with each pet into the routine from the very beginning — rather than treating the pair as a single unit from day one — sets a healthier pattern early. This doesn't mean keeping the new arrival and the existing pet apart unnecessarily; a gradual, well-managed introduction and plenty of supervised shared time is still the right approach for building a good relationship between them. It simply means making sure "time with the new pet" and "time with the existing pet" both still happen separately and regularly, alongside the shared time, so neither pet's sense of security ends up resting entirely on the other.
Enrichment that works whether one pet or both are around
A practical, low-effort piece of the puzzle is making sure each pet has access to enrichment that doesn't require their housemate's presence or participation. A puzzle feeder, a long-lasting chew, or a feeding routine that occupies a dog mentally for a stretch of time gives them something engaging to do during a deliberate separation, which makes the separation itself less of a void and more of a normal, tolerable part of the day. The Big Slow Puzzle Feeder for dogs and the Big Hunt Felt Puzzle Feeder for cats both work well specifically because they're solo activities by design — giving each pet their own feeding-time enrichment task means mealtimes themselves become a built-in period of calm, productive separation, several times a day, without any extra effort required beyond using the right feeder.
Rescue pairs adopted together: a slightly different starting point
Bonded pairs adopted together from a rescue — often littermates or dogs who were housed together for a long stretch before adoption — arrive with an existing bond already fully formed, which is different from two pets who've grown into closeness gradually within your own household. Rescues often place these pairs together specifically because separating them at the point of adoption would be its own source of trauma, which is a reasonable adoption decision, but it does mean the independence-building work covered in this guide usually needs to start from a more entrenched position than it would with, say, a single resident dog and a new puppy, since the pair has had months or years of uninterrupted togetherness to settle into before you ever meet them.
The approach doesn't change, but the pace often needs to. Starting with genuinely very short separations — a few minutes rather than ten or fifteen — and building up more gradually than you might with a less tightly bonded pair tends to go better, since pushing too fast with a pair who've never truly been apart can trigger a level of panic that sets the whole process back. Patience here pays off; a bonded rescue pair who gradually learn that separation is tolerable, at their own pace, generally end up just as settled as any other pair, just via a longer runway. It's also worth mentioning to a rescue organisation or the previous owner, if you have any contact with them, that you're planning to work on independence gradually — they may have useful background on how the pair coped with any prior separations, which can save you some trial and error.
When one pet in a bonded pair passes away or needs to be rehomed
This is one of the hardest versions of this problem, and worth addressing directly because it's a genuinely common situation multi-pet households eventually face. A surviving pet who's never had to be independent can show real grief and distress after losing a long-term companion — reduced appetite, lethargy, searching behaviour, vocalising, or a noticeable drop in overall engagement with the household. Some of this is a normal grieving process that eases with time, routine, and extra attention, but it's also, in effect, the most extreme version of the separation this whole guide is about, arriving suddenly and without any prior practice.
If you know a pairing is especially close and one pet is elderly or unwell, it's worth gently starting some of the independence-building practices in this guide well before it becomes necessary, purely so the surviving pet has at least some prior experience of managing time alone if the worst happens. For a pet who's already lost a companion and is struggling, treating the situation much like starting from scratch with separation training — short, calm, gradually lengthening periods alone, paired with extra one-on-one attention and enrichment — is the right approach, and it's worth involving a vet if grief-related appetite loss or lethargy doesn't start easing within a week or two.
Three or more pets: the maths gets more complicated, not less
Everything above assumes a pair, but households with three or more pets face a slightly different challenge: rather than one bond to manage, there can be multiple overlapping pairings, some closer than others, and a dynamic where removing any one pet from the house temporarily affects the remaining group in ways that aren't always obvious in advance. It's worth identifying, honestly, which pairings within a larger group are genuinely close versus simply tolerant of each other, since the independence-building steps in this guide matter most for the pairs with real over-bonding risk, not necessarily every possible combination in the house.
Rotating which pet gets individual time and training on any given day, rather than trying to manage every pet's individual needs every single day, keeps this realistic for a larger household without the whole routine collapsing from sheer logistics. Over a week, every pet still gets meaningful one-on-one time; it just doesn't all have to happen within any single day.
What not to do: well-meaning mistakes that reinforce the anxiety
A few common instincts actually make pet-to-pet separation anxiety worse rather than better. Making a big, emotional fuss at the moment of separation or reunion — a long, dramatic goodbye, an excited, high-energy greeting the second the pets are back together — inadvertently signals that separation is a significant event worth being anxious about, reinforcing exactly the pattern you're trying to soften. Keeping both the separation and the reunion calm and low-key, almost uneventful, helps far more than it seems like it should.
Avoiding separation altogether because it's easier in the moment is another common trap — it feels kind, but it means the pair never builds any tolerance for it, which simply guarantees the first genuinely necessary separation (a vet stay, a different boarding situation, one pet being unwell and needing to be kept apart) will be significantly harder on both animals than it needed to be. Treating scheduled, brief, calm separations as a routine and ongoing part of life, rather than an occasional ordeal, is what actually builds resilience over time.
A note on breeds and temperaments that run more dependent
Some breeds and individual temperaments are simply more prone to strong attachment generally, and it's worth knowing this isn't a flaw to train out so much as a trait to work with. Breeds developed for close working partnership with people or other animals — many herding and companion breeds among them — often form intense bonds more readily than independent-minded breeds, and that same tendency that makes them wonderful, attentive companions can also make them more susceptible to over-bonding with a housemate if the independence-building steps above aren't part of the routine from early on. This isn't a reason to avoid getting a second pet of a naturally bonding breed, just a reason to be a little more deliberate and consistent about building in separation practice from the start rather than assuming it'll sort itself out.
When professional help is worth bringing in
Mild, improving-with-practice unsettledness during separation is something most multi-pet households can work through with the steps above over a matter of weeks. It's worth involving a vet or a qualified behaviourist if distress is severe (significant vocalising, destructive behaviour, self-injury, loss of bladder or bowel control specifically tied to separation), if it's not improving or is getting worse despite consistent practice, or if one pet's anxiety is clearly affecting their physical health — persistent loss of appetite, significant weight change, or ongoing signs of chronic stress. A vet check is also sensible before assuming any sudden behavioural change is purely anxiety-related, since some medical conditions can produce similar-looking distress, and ruling those out first means any behavioural work you then put in is actually targeting the right problem.
Boarding, vet stays, and travel: the real-world test of this work
The genuine payoff of all this groundwork tends to show up precisely when it's needed most: a vet admission, a boarding stay, one pet travelling while the other stays home. Pets who've had regular, calm practice at being apart handle these genuinely unavoidable separations considerably better than pets who've never once been apart, and the difference shows up clearly in things like how quickly a boarded dog settles, or how calmly a pet left behind copes with a housemate's temporary absence. It's worth using a pet's existing solo walk, as covered earlier, as a dry run before any planned separation of this kind — the Big Trail No-Pull Harness is worth having for exactly these individual outings, since a dog who's used to solo walks on familiar gear tends to settle into any other kind of solo time, including a vet or boarding stay, with noticeably less fuss than one for whom every walk has only ever happened as a pair.
A realistic weekly routine for building healthier independence
None of this needs to dominate daily life to work. A sensible starting routine looks something like: brief separations (ten to twenty minutes, calm and low-key) two or three times a week to begin with, building up gradually as both pets settle more easily; one walk a week per dog done individually rather than together, where that's logistically workable; a few minutes of one-on-one training or focused attention per pet most days; separate sleeping or resting spaces, at least to start, even if full separate rooms isn't practical; and enrichment — puzzle feeders, chews, solo play — available during every deliberate separation so the time apart is occupied rather than simply endured.
Scaling the frequency and length of separations up gradually, based on how settled both pets genuinely seem rather than on a fixed schedule, tends to work better than jumping straight to long separations before either pet has had a chance to build confidence at shorter ones. Keeping a simple mental note, or even a brief written log for the first few weeks, of how each pet handled each separation — settled quickly, took a while, didn't settle at all — makes it much easier to judge when to extend the time apart versus when to hold steady a little longer at the current length, rather than guessing.
The aim throughout is a household where a close bond between pets is a source of comfort, not a source of panic the moment it's interrupted — which, done well, benefits the pets' wellbeing and makes the household's day-to-day logistics (vet visits, boarding, one pet needing to travel without the other) considerably less stressful for everyone involved, pets and owners alike.
Q: Will getting a second dog cure my current dog's separation anxiety?
A: Research specifically looking at this found the opposite is more often true — dogs in multi-dog households vocalised more when left alone, not less, particularly in the first hour. A second dog can help with boredom and general understimulation, which is a different problem, but it isn't a reliable fix for genuine separation anxiety and can sometimes create a second anxious attachment instead.
Q: My two dogs are littermates and seem inseparable — is that automatically a problem?
A: Not automatically, but it's worth watching closely. A close bond is healthy; genuine panic when separated, fear of new people or situations the pair hasn't faced together, or reactivity toward unfamiliar dogs are the signs that point toward littermate syndrome rather than simple closeness. Building in deliberate, regular individual time and separate training early is the most effective way to prevent it from developing further.
Q: My cat seems fine being left alone by me but gets distressed when my other cat goes to the vet — is that separation anxiety?
A: It can be — cats are often quieter about distress than dogs, so this kind of companion-specific reaction (reduced eating, excessive grooming, hiding for longer than usual, specifically when the other cat is removed) is a real and recognisable pattern. Giving each cat their own secure resting spot and some individual routine helps build the same kind of independent confidence that benefits dogs in this situation.
Q: Is it cruel to deliberately separate two pets who clearly enjoy each other's company?
A: No — the goal isn't to reduce how much time they spend together overall, just to make sure neither pet's sense of security depends entirely on the other being present. Brief, calm, regular separations alongside plenty of continued shared time actually protects the bond in the long run, by making sure an unavoidable separation later doesn't become a crisis for either animal.
Q: How long does it typically take to see improvement once we start working on this?
A: Many households see some easing within a few weeks of consistent practice, particularly with milder unsettledness rather than severe distress. Gradual, steady improvement with occasional setbacks is the realistic pattern to expect; if there's no improvement at all after several weeks of genuinely consistent effort, or if distress is severe, that's the point to bring in a vet or qualified behaviourist rather than continuing to self-manage it.
— Joseph, The Big Pet Shop, Bacup, Lancashire 🐾