Need=no; Ok=yes. The nutrition of an infant can be as simple or complex as u want to make it. Breast milk will provide the proper balance of fluid & nutrients without supplemental fluids for at least the first year. Formula is patterned after breast milk & functions the same for fluid need. A normal baby, wetting diapers @ least every 6h is fine. A little water given by u, a friend or relative is a joyful expernc.