Seven-month-old baby development standards Seven-month-old babies are a critical period for the baby\’s growth and development. Parents need to pay attention to the baby\’s development standards. Early prevention and intervention will help the baby become a healthy and happy child. The following introduces the development standards of seven-month-old babies from four aspects and how to promote healthy physical development. 1. Growth and weight Generally speaking, the weight of a seven-month-old baby is between 6.5-9.3 kg, and the length is between 62.5-7 kg.