A 70-day-old infant can make some progress in movement, hearing and vision, such as learning to roll over, judging sound sources, and observing objects. 1. Motor: 70-day-old infants have learned to roll over and begin to try to hold their heads up. They can hold their heads upright for a few moments, lift their heads off the bed when lying on their stomachs, and hold toys in their hands for a few moments when placing them in their hands. 2. Hearing: If there is a sound around them, 70-day-old infants can accurately determine the source of the sound and turn their heads to look for it. 3. Visual acuity: 70-day-olds can see moving objects in a blurry manner, can follow objects horizontally with their eyes, and can draw attention to large, brightly colored toys immediately when they are placed in front of them. Parents are advised to carefully observe the growth and development of their infants and follow up with them regularly in the pediatric outpatient clinic. If the infant’s development is delayed, regular treatment should be provided as soon as possible after the abnormality is detected.