Question: how much weight should a 4 month old gain in a month?
Answer: 1 to 4 months: Babies usually gain 1 1/2 to 2 pounds and grow 1 to 1 1/2 inches each month. During this time, your baby may begin looking chubby; however as her activity level increases, those baby rolls will soon be replaced by developing muscle. By 6 months: Most babies have doubled their birth weight.