Mixed feeding of infants at three and a half months should be accompanied by appropriate feeding of water between feeds. It is not recommended to feed water immediately after breastfeeding because the infant’s stomach capacity is small and drinking water at this time can lead to a feeling of fullness. Breastmilk also contains a certain amount of water, so it is not advocated to drink a lot of water before the infant is 4 months old. For mixed feeding newborns can drink a small amount of water, three and a half months of newborns due to the relatively perfect development of gastrointestinal function, you can choose to drink water between meals, start drinking about 10 ml or so, with the age of the month gradually increase the amount of water. Mixed feeding, pay attention not to eat too full, to avoid the formation of indigestion symptoms, 4 months can be appropriate to add complementary foods, pay attention to the principle of from less to more from one to many, about the knowledge of feeding is recommended to consult the child health department if necessary.