Money. They like money. Everyone can use money. I have a nephew who is 29 years old - he came into the family at 13 and so wasn’t really part of the whole gift/celebration thing and didn’t visit with our family much. But he was still a kid and I wanted him to feel like someone was thinking about him on holidays. Now he’s got a wife and a baby and he’s a full ass adult and I don’t care. I still give him $50 on his birthday and Xmas. Because I still love him. Maybe he uses it to gas up his car. Maybe he uses it for diapers. Maybe he buys himself something with it - doesn’t matter. My nieces and nephews always get a present from me no matter their age, but after 13, everyone likes money.