Cat Chat Feline Forum

So I have had two cats (both girls) for about3 months now (got them as little babies) and I am just now getting there brother (he is from the same litter as them and looks exactly like one of them) because the home he had wasn’t right. One of my cats (the one that looks the same as him) is being nice to him and the other one is being mean to him and is trying to claw at her sister. Might I mention the cat I am now receiving is there brother. All of them are fixed. There brother is being nice to both of them and is more of a beta cat than the alpha. He towers over them due to the growth hormones they had to give to him to save his life (long story short he had a poisonous cactus in his paw and they had to do surgery about a week after he was born) I am confused why the two cats that grew up with each other (well for 4 months from birth at least) are being mean to each other. Below are pictures of the two cats I have had for a while and the one I just got. (No it’s not the same cat)

Unfortunately just because they are siblings doesn't mean you can just put them together and there will be a happy reunion, after being separated for 3 months and him being in a different house means they may not recognize him, so you will have to do gradual introductions