My baby was born on 34 weeks with birth weight of 2.14. He is 3 months and 22 days old now his weight is 5.1. Is it correct weight or whether he is in low percentile

A. Let’s take it four months overall and your child has gained more than 3 kg so this is a healthy weight for the current age of your child the minimum expectation is 2 kg and your child has gained more than that which is very healthy