17/11/2025
Long read but worth it! 💯
Below is the full blog on littermate syndrome, which will be available on our website shortly. I’m sharing it here because a fair few people have asked whether we’ve lost our marbles bringing home two puppies from the same litter. Fear not. This isn’t our first rodeo, and certainly not Karen’s. She currently has three other sets of littermates in her care and hasn’t had a single issue, because the secret isn’t in avoiding littermates altogether but in managing them properly. It’s about training each dog as an individual as well as a team, building confidence separately, and steering their development with calm, competent leadership. Most pet owners simply don’t have that depth of experience, which is why littermate syndrome can catch them off guard. So, for those curious or concerned, here’s the blog you’ve been asking about.
Littermate Syndrome: What It Is, What It Isn’t, and How to Raise Two Puppies Without the Panic
If you’ve ever mentioned bringing home two puppies at once, you’ll know the look. Eyebrows lift, voices lower, and someone whispers, “Watch out for littermate syndrome.” It’s become one of those phrases that floats around dog circles like a cautionary ghost story, often shared with more drama than detail.
But what is it actually? Is it guaranteed chaos? And, more importantly, how do you raise two puppies successfully without stumbling into the very problems people worry about?
Let’s unpack the facts, sweep away the myths, and lay out a clear, calm plan for anyone welcoming a double helping of puppyhood.
What Is Littermate Syndrome?
Littermate syndrome isn’t a formal clinical diagnosis. Rather, it’s a cluster of behavioural challenges that can sometimes develop when two puppies of the same age (usually siblings) are raised together. The key word is sometimes.
The concerns generally centre around:
• Over-bonding with one another instead of bonding with humans
• Anxiety and distress when separated
• Difficulty developing independence
• Poor social skills with unfamiliar dogs
• Slower progress in obedience or recall
• Heightened reactivity as they reach adolescence
Think of it as two toddlers clinging to each other in the corner of the playground instead of exploring the world. The friendship is adorable, but the dependency can stunt their confidence.
What Littermate Syndrome Is Not
It’s not inevitable.
It’s not a guarantee your dogs will have issues.
It’s not something that magically appears at a certain age no matter what you do.
The problems associated with littermate syndrome usually arise from management, not mere biology. The puppies don’t cause the syndrome. The structure (or lack of it) does.
When puppies are allowed to raise one another, when they’re together 24/7, when every novelty is met as a bonded pair rather than as individuals, that is the fertile soil where issues grow.
Raise them intentionally and thoughtfully, and the risk drops dramatically.
What You Should Do When Raising Two Puppies
1. Build Two Dogs, Not One with Two Heads
Each pup needs time to grow their own mind, their own confidence, and their own relationship with you. That means:
• Separate training sessions
• Separate walks (most of the time)
• Separate crate time
• Separate exposure to the world
Sometimes this feels like you’ve adopted a full-time job as a canine event coordinator, but it pays off.
2. Crate Separately (Preferably in the Same Room at First)
Two crates. Two safe spaces.
Over time, gradually increase the distance between them, allowing each pup to develop their own sense of security.
Sleeping in the same crate may look sweet for a fortnight, but it doesn’t build emotional independence.
3. Training: Little and Often
Each pup should learn to:
• Settle without their sibling
• Walk on a loose lead without the other pulling them along
• Focus on you without glancing at their built-in cheerleader
• Play with you individually
• Work for rewards separately
You’re helping them become confident soloists before they become a harmonious duet.
4. Socialise Separately as Well as Together
Let each dog meet:
• New people
• New dogs
• New sounds
• New environments
on their own terms.
When they always arrive as a pair, one often leads and the other becomes the shadow.
5. Create Structured “Together Time”
Being together shouldn’t be chaotic free-for-all puppy anarchy.
It should be:
• Calm play
• Parallel walks
• Shared rest time (once they can settle properly)
• Joint training once both are competent individually
Think of it as teaching them good manners with each other, not just with humans.
6. Keep an Eye on Their Personalities as They Develop
Littermates often hit adolescence like a tiny rugby team discovering caffeine. Along the way, keep watch for:
• One pup becoming overly dominant
• One pup becoming overly dependent
• Tensions during high arousal times (feeding, play, greetings)
Addressing issues early keeps them small.
7. Prioritise Engagement and Bonding with You
Each pup should see you as their compass.
One-to-one time isn’t just training; it’s bonding:
• Hand-feeding
• Gentle engagement games
• Scentwork
• Play sessions
• Quiet time together
If the pups become more expressive with you than with each other, you’re winning.
What You Shouldn’t Do When Raising Littermates
1. Don’t Let Them Enter the World as a Permanent Double-Act
Walking them as a pair from day one
Plus
Training them side by side
Plus
Sleeping together
Plus
Playing together endlessly
Equals
Dependency.
Cotton wool may feel kind, but independence grows through space.
2. Don’t Ignore Early Signs of Trouble
Common red flags include:
• One pup guarding the other
• One pup following the other everywhere
• Panic when separated
• Tension or competition at feeding time
• One becoming the “quiet one” who doesn’t explore
If you notice it, address it. Problems don’t evaporate with age; they grow teeth.
3. Don’t Let Them Teach Each Other Bad Habits
If one learns to bark at strangers, pull on the lead, or herd passing joggers, the other usually picks it up at lightning speed.
Interrupt poor behaviour early, work separately, and reinforce what you do want.
4. Don’t Allow Rough Play to Become the Default Interaction
Puppies who wrestle from dawn till dusk can become overstimulated and reactive. Play is fine. Chaos is not.
Teach them to play with you, not only with each other.
5. Don’t Over-Focus on Them Being Siblings
The fact that they’re related doesn’t doom them. It doesn’t define them.
Treat them as two individual dogs, not a matched set of furry ornaments.
When Two Puppies Go Right
When raised well, littermates often develop a bond that is both healthy and heart-warming. You end up with:
• Two confident dogs
• Two independent dogs
• Two dogs who can work alone or together
• A household that feels fuller, richer, and more alive
• A pack dynamic shaped by humans, not chaos
And you get to enjoy one of life’s rarer privileges: watching two dogs grow up side by side with all the stability and structure they need to flourish.
Final Thoughts
Littermate syndrome isn’t a sentence; it’s a scenario that can emerge when structure is missing. If you provide leadership, independence, boundaries, and thoughtful development, you can raise two puppies who grow into confident individuals that complement rather than consume each other.
Two puppies is more work.
Two puppies is more planning.
But two puppies, raised properly, is twice the joy and double the potential.
And when people ask, “Aren’t you worried about littermate syndrome?”
You can smile and say:
“Not at all. We’re doing it properly.”
