My daughter is 5 yrs old but she has very low weight i.e. 13 kg. she is very normal and is active in all work she does. she has healthy eating habits?

Growth parameters: To review with her pediatrician are height, head circumference, body mass index, & velocity of growth of all parameters. If her height & weight remain proportional, with bmi, head circumference & development within average (25th-75th %ile), she may yet reach the 5th %ile or >. Her small stature may be ok if rate of growth remains normal. If she has low weight for height, an evaluation is needed.