Weight of the child is not mentioned. If the weight of the child is adequate as per age (your dr will inform you this) and child is active, passing urine adequately then no need to wake up at night. Let the child sleep. What should be followed is demand feed. If the baby is hungry then and then only give feed to the baby. Many times they can feel hungry within 1/2hr also. No need to wake the child from sleep and give milk. 2hr/3hr feeding is only done in the initial days of life when weight is less than 2.5kg. A baby is gaining good weight gain and passing adequate urine should not be disturbed from sleep to feed and only demand feeding should be followed.

We advise 'demand feeding' pattern for a 2-3 month old healthy baby, which means feed the baby when it's hungry. But be sure to catch the early hunger cues in your baby and feed him. As babies grow older, they tend to sleep for little longer hours. Also if a baby is formula fed, they sleep for longer hours versus breast milk fed babies because formula milk takes little longer than breastmilk to get digested. If your baby's gaining weight as per his growth charts and active,  follow his hunger cues and feed him.