Can anyone pls tell me wat is the average weight for 5months old baby bcz my baby is a premiee..he was born in 7th month of pregnancy..he was put on ventilator for 5days nd also kept in nursery for 15days at the tym of his birth.. his birth weight was 1.5 kg ...still his weight is 6.5kg...he has completed his 5months recently..i m always vry concerned about his weight..is it ok or not...if not so wat can i do to increase his weight..?.