My four months old boy is on combination feeding 4oz four times a day(enfamil) plus breastfeed. he is not taking breast now. feeds only in sleep.

Feeds only in sleep?: Normal, healthy children do not need to eat or drink in the night time (they should just be sleeping). Babies can sleep well at night by 3 months of age, which means sleeping about 6 hours straight. When they get a few months older, they usually "sleep all night" without waking up to eat. So, except for young babies, normal children need not eat or drink between bedtime and morning.

Stop that pattern: Infants cannot be asleep & be eating.Many create a nasty habit as baby uses feeding as their transitional crutch while they glide into sleep.It is important to stop this & make sure baby stays up for at least a 1/2 hour before they sleep, so they can establish a good day feeding pattern. It is best if you put baby down & console it from a short distance if it is fussy.Don't teach it to use rocking