DD is 8.5 yrs. Today we went shopping and I realised that clothes don't really fit very well for her age. She's about 1.3m high so average but her age but weight is 25.4 kg. which is on the 25th line. She's not a great eater never has been. She does a lot of sport, swimming and gymnastics and sport most days at school. To me she is quite lean and very strong. Do I worry that she's a bit under weight? By about 2 kgs. Or is that acceptable within the normal range?