Interpretation of the standard value of development of four-month-old babies. Four-month-old babies are a period of rapid development. Parents need to understand the standard development values of their babies and take corresponding measures to promote the healthy growth of their babies. This article will elaborate on the four-month-old baby\’s development standards and how to promote the baby\’s healthy growth from four aspects. Physical Development The standard values of physical development for a four-month-old baby include weight, height and head circumference. According to statistics, the average weight of a four-month-old baby is 6-7 kg and the height is 61-6