Thanks for all the input! My nephew would really love to have a cat, but I don't think that's the best idea since our cats all get along really well and I don't want to change a good thing. Plus, he can help care for and play with the cats we have, and they like having someone who plays with them often.

He is leaning towards a leopard gecko for his own pet. I've been reading up on how to care for them and am nervous about having a cold-blooded pet. As long as you have a heat source and cooler area for them, is it pretty easy to keep them the right temperature? I've never had a reptile before!

I'm going to have my nephew read up on leopard geckos before we get one so he can help select the right home for it, etc. I'll update when we get the pet (maybe next week) with pictures!