Good question. I've wondered this myself. I did a an Internet search with this question, and there are several hits if you are interested in reading.

My dog goes to the dog park and when a dog who has been absent for sometime does come, the other dogs seem to remember him. But as for long-term absence and siblings or parents, I don't know. Would my dog remember his mother or siblings if he saw them? I doubt it.

I dunno about siblings or their moms but they do remember people!! My darling stepdaughter was with me when we picked my pup out at the breeders and was around quite a bit during his first year. But then I moved and then she moved as well and now we only see other infrequently - maybe just a few times a year and not always with the dog. But when he does see her, he for sure knows who she is!! He gets very excited - much more so than he does when greeting other people he knows. Just about turns himself inside out and whines happily like he does when he sees me after an extended absence. He never acts like that with anyone else ;-)

I think they remember. In my regular home they are forbidden from jumping on furniture and they observe rule. In country home they can jump as they please, muddy or not, and they enjoy the privilege. They are never confused about where they are and what rule is in effect. Of course, their Mom is a little biased and she wholeheartedly believes thy are direct Einstein descendants...

We had a lab that lived with his mother and sister until he was 7 months old. His sister was a yellow lab - and every time our dog saw a yellow lab, he got excited, thinking it was his sister! He didn't act that way toward any other dogs. We did visit on occasion, and he always went nuts when he saw her. Oddly, he didn't react as strongly to his mother.

Sweet story AnnKH. I would bet dogs have a keener sense about such things than cats. But I could be wrong. I know where Peach's sister is but it is miles away and I haven't had contact with her adoptive parents except for one phone call at that time.

On Sunday I took my dogs to my niece's house. She has a cat. One of my dogs used to see that cat one to two times a week 8 years ago. The cat and dog walked up to each other, went nose to nose and looked at each other for a moment. Then each turned and walked away. They were clearly greeting each other! My other dog (who wasn't familiar with the cat) kept her distance and didn't approach the cat. It was fascinating to watch!

I don't know about their animal families, but they definitely remember their "human" siblings. My son moved away 2 years ago, but each time he comes home our Beagle Max greets him in a very familiar way, Then he wants to go for a walk on the lake. Our son thinks he's sort of silly, yet LOVES the attention.

This was them- son got him involved in the "selfie" movement. Note Max: When my son is home, he tries hard never too get farther than this away from him. Sweet.

PS- don't worry about the Easy leader. It's his "good dog leash", and Son needs it to keep him calm in the car.

That pic is priceless lol

Yes, they remember.

I had one kitten parted from his sibling for about three months. One day a friend of mine who'd taken on the brother brought the brother over They were all over each other remembering each other. My kitten ignored other cats, otherwise. Total re-bonding scrimmage time!

I had another cat earlier in life. I went off to school for a semester, and didn't get home for any breaks until the end of semester. I came home, and that (neutered) cat spent the next several hours trying to hump my foot, or arm, or whatever he could reach! He was that overjoyed!

I can't see any reason why they'd be less inclined to remember siblings than humans.

Some do, some don't, but even with dogs who remember a mum or sibling, they usually do not remember the relationship.

a year or so after i adopted one of my dane girls, olivia, from rescue, i was contacted via facebook by her former owners. they had lost their home to foreclosure and had to give up both of their danes. olivia was 8 years old at the time and they were devastated.

after talking to her a few times, i invited them to visit if they were in our area. they came out one day (mom, dad, 4 young sons). when they got out of their car, olivia was just a big ball of wiggles and tail wags. they came into the house, we all sat on the floor, and olivia went from one to the other to the other until she had leaned on and given slobbery kisses to every one of them. it was so sweet to watch and they were thrilled to see her and so relieved that she was being well cared for and was happy. they stayed a couple of hours. when they left, the danes and i escorted them out to their car. they drove away and olivia turned and walked into the house with us and took a nap. i had a few people tell me it was wrong to do but she did not seem the least bit affected by it.

We had a poodle when I was growing up many years ago. She was bred one time and most of her puppies went to neighbors or family members. Whenever she saw one of her pups as an adult, she wanted nothing to do with them! Have no clue why.

I often wonder too. I stay in touch with three people who have the litter mates of one of my bulldogs. One day I know I'm going to meet at least two of them since we all live within an hour or so of each other.

Wonder how my not so social pup is gonna react.

Read Only one Woof by James Herriot.