An alligator with pets?

The American Alligator (Alligator mississipiensis) can grow up to a foot a year. Even at a young age they are aggressive and will try to bite. They will do this in order to protect themselves even if they are "used to people" and will try to eat anything they think may be small enough (like a dog or cat). You said your brother is going to get an apartment but no apartment is big enough to hold an alligator once it starts to get large. The only time you should ever own an animal like this is if you are a trained and licensed animal keeper. This alligator is a very real threat to your other pets and more importantly (once it grows more) to people who may be near it, your brother for instance.