I have 5 kids. 3 boys and 2 girls. My oldest (step)son is 6'4". was captain of his high school soccer team and played on State Champ football team. He just lost 100 lbs that he had gained the first 3 years of college. All I have to say to him on that is that I am very happy for him. He Stopped listening to what I told him about working out when he was in 7th grade. My oldest daughter never listened to a thing I had to say to her about anything. My two younger boys, both18, exercise regularly. One is in college and does the normal screw around workouts that most young people do. My other18 year old son works out intently With weights, overtraining for peak fitness. I have given him a copy of starting strength and tried to encourage him to eat more and lift heavier. I make sure there is plenty of food in the fridge and he has access to the weights.
Youngest daughter listened to me and spent about a month squatting, then got bored of it wanted to run and do yoga....so be it. My wife was a cross fitter. She runs with my daughter.
I get the weights pretty much to myself.