WIBTAH for not telling my brother i'm moving his cat to another place

My brother and i are pretty much no contact. We're not living together anymore since a long while and i also haven't seen him since a while. Last time i did was when he once again made my mother cry and ever since i haven't seen or heard from him again.

I miss him but i'm also done with him for all the pain he has caused.

Now here is the problem. I still have his cat. He lives in a place where animals aren't allowed, which is why we (my mom and i) are taking care of the cat. He hasn't checked on him or how he's doing since the last Incident i mentioned before. I know he loves his cat, but obviously not enough to ask about him.

For personal reasons, we want to move out. We don't know where yet, but the city i'm hoping for is 5 hours away. I also don't want him to know that we are moving. I don't want to see him or talk to him either. Which means i either have to take his cat with me, or leave it at his doorstep and let him deal with it. I love that cat so i don't want it to end up on the street or worse. But i'm also not sure if i should just take it with me without telling him. I doubt he would ever find out anyways since he never texted me to ask about it and if it's doing okay.

So my question is, what should i do? And would i be the AH for not telling him and just taking his cat with me?