my twin children are now three months old. what changes likely to happen in their growth and behaviour

A. the average birth weight of neonates is about 3 kg. during the first few days after birth, the newborn loses extracellular fluid equivalent to about 10% of the body weight. most infants regain their birth weight by the age of 10 days. subsequently, they gain weight at a rate of approximately 25 to 30 g per day for the first 3 months of life. thereafter they gain about 400 g weight every month, for the remaining part of the first year. an infant usually doudbles his birth weight (taken as 3 kg) by the age of 5 months. the birth weight triples at 1 year and is four times at 2 years of age. the weight of a child at the age of three years is usually five times that of the birth weight.