Sisters fighting

Does anyone have any knowledge of behaviour of dogs from the same litter? Our pup leia has met one of her sisters a few times and the last two times they've been together they start to fight and not just playing it's aggressive! The first few times they loved eachother and had a great time but now we can't have them together at all! Leia is the bigger pup so maybe it's a dominance thing but just wondered if anyone could tell me anything else? Thanks!

Sibling behaviour can be different from interactions with other dogs. It's the reason why at our rescue we don't rehome siblings unless they are an older, established pair.

I'm not sure if there is clear scientific research but one theory I find plausible is that siblings learn to rough and tumble together from the word go and don't seem to have the same respect and cut off point as unrelated dogs have. That's clearly not a hard and fast rule, you clearly do have siblings who do learn where the line is, but others don't.

There may not be masses you can do about it, other than keep them apart. Yes, it's possible to do some retraining but it may prove more effort than the occasional meeting merits. Keep her well socialised with others and her sister should be the exception rather than the rule with her doggy interactions.

Thanks so much, it would just be nice for them to be able to play but her best interests are the most important thing so I'll maybe just keep them apart for now!