My parents would send seperate cards out to my cousins' kids when they were small, and include a few bucks. They stopped after a while because of age, but frankly, I think it was because they never received a thank you card. We hardly saw them, but mom didn't think kids should suffer because of their parents' attitude.

I don't have much family left, but I do send cards out to the remaining aunts and uncles and some cousins. Mostly, the 200 cards we send out are to PT and friends I've known for decades.