My daughter is 9 1/2 and has a very cute toned body.  She has swcah.  She was off the charts  on the high end for height and weight, as a baby, but thinned out when she started running(I don’t think she ever walked!) She is very athletic-loves sports.  She has played soccer since she was 5, basketball for 3 seasons, baseball- two season, and done some swimming, and gymnastics.  I don’t worry about the puberty weight gain with her because she is so active!   She snacks alot on salty food, but also likes fruit and other healthy snacks.