If you were going to get your lo a small pet, what would you get?

Los (3 and 6) had a beta fish for about a year and a half that just died. We also have two dogs, but they really liked having a low-ish maintenance pet that lived in their shared room. We already have a tank, but are thinking about other pets that could live inside. I had a hamster growing up and don’t remember it being too much work, and it could be a bit more fun/interactive than a fish...

What would you get?