too small to put together?

Quick question, I was just given a leo gecko and he is way smaller then my other one and right now I have them in differant tanks but my friend said I can put them together but I'm thinking the guy he gave me is soo small he might be lunch for my other guy.
So the question is can I put the 2 together?
Mark

Don't put them together. Wait until they are of close size to put them together. Also, don't house them together if they're both male. That will lead to some nasty fighting that you're not gonna want.