Hi there, Noted your query. The average weight for a 5 yr old would be about 18 kgs. At the same time birth weight also plays a role and she seems to not have been a very big baby at birth.Its alright for her not to like biscuits or chocolates as they have empty calories and do not make your child healthy. 1. If your child is healthy, active and doing well otherwise, do not worry too much. 2. Get her checked for iron deficiency anemia as this decreases appetite, causes lethargy and lack of interest in any activity. 3. Give her a course of deworming after seeing your pediatrician. 4.Give her some good sports activity like swimming or tennis, table tennis lessons. This builds her bones and muscles and will stimulate appetite. 5. Diet.. Stick to 3 meals per day. Plan a heavy wholesome breakfast of toast or eggs/ muesli, etc with a glass of milk and fruits..Give a nutritious lunch with rice, vegetables, greens, meat, a light evening snack of fruits and milk and a good supper followed by a glass of whole milk.Do not allow snacking in between. There will definitely be some problems initially when you start but she will get better and you will have a happy healthy child. Hope you ARE reassured. Happy parenting. Bye