J.G.
Does he have problems sharing at daycare? Talk to the teachers about it and ask what they are doing to correct behavior. I say this because the way to correct any type of behavior is consistency! I know all too well about the cousin thing and the sharing issue. I still have them with my 3 year old too! What I do when the cousins are together is reinforce the "take turn" rule, and even try to engage them in more activites where they can both do the same thing if sharing is a BIG problem. Like play-doh, for instance, or bike riding, so long as there are two bikes. =) Something else I do with the cousins, is tell them BOTH, that if they can't share, then X toy will get put away and NO ONE gets to play with it. I have ruffled some feathers of my nephew's mom, but you know what... too bad. I have to look out for my kid. =) Don't be afraid to step up and tell the cousin to take turns too. I know it's hard to teach your own though esp. when the other doesn't share. Hang in there. They eventually learn how to share.