At that age, babies need a lot of sleep during day & night. He will need to nap a lot during the day but at night, make the environment very quiet & dark. This is what worked for my son after awhile. My son liked to be swaddled so I would swaddle him and then hold him or rock him with low light & noise (maybe white noise would help) and he would eventually fall asleep. Essentially, make the environment during the day different than at night (at night low to no light, white noise, little stimulation, etc.; during the day, more activity, higher light level). Eventually he will catch on to the difference. I, too, breastfed, and my son breastfed quite a number of times during the night (& day!), which is normal and what he needs. I would consider it unusual if he slept through the night at this age while breastfed. Their tummies only hold the milk for 1 1/2 hours so they need to eat more often than formula fed babies.