chinchillas aren't the best pets for children. rabbits are awesome. your brother already has experiance with them. why not get another bun? rats are great! be sure to get atleast two. they are socail animals and need the company of another rat. gerbils and hamsters aren't the best for children either. they can bite and some kids don't know how to properly handle such a small animal. i'm glad a ferret is out of the question. they are not good with small children. they need a lot of attention, lots of room and yes, they can smell. a parakeet makes a nice pet. they don't need a lot of room, are easy to keep and feed. be sure that your brother knows how to properly handle a small bird though.

GOOD LUCK!!!