my children was pre mature when she was born. her wait was 1700 gm but now she is 4 kg 100 gm. but she's still low wait at her age so what can I do make her wait gain

A. Hi You baby has gained good weight as per the birth weight. The catch-up growth may take time. so not don't compare with babies born with normal weight at birth. best way to track growth is by plotting weight on a growth chart