My children are grown, with children of their own. But I still talk to them almost daily, visit, vacation with them. I tell them I love them, and some financial support has happened, even though they all have good jobs. You can't take it with you, and I would rather them live a bit better now, than in the future (hopefully far, in the future!).
I respect my children, but I am not afraid to admonish or give them advice even at this age. Fortunately, they take it a lot better than they did when they were teens!
I also pray for my children, their spouses, their children and their future spouses. I think prayer is the most important thing to do for our children, because prayer is the tool God has given us to change the world!