my baby girl's birth weight was 2.945 kg ....now she is 3 months old and weighs 5.225 kg...is she underweight? or is it normal

A. 3 months and weight is around 5.2 kgs good weight gain baby should double the birth Weight at 4-6 months and three times the birth Weight at completing one year exclusively Breast feed recommended for six months mother milk helps in weight gain