My 2 month old baby boy does not cry for feed during night and is in deep sleep. This habit started at 1.5 months age . He sleeps around 10- 11 PM in night and does not voluntarily wake up for feed . I wake him up every 3 hours and feed him but he just feeds for 5-6 mins and dozes off again. But once he wakes up he has 3 pees over period of 3 hours in morning. He feeds well during day time and naps very little. I'm worried that he might not gain weight well and might have dehydration. His birth weight was 3.6kg and now at 2 months he is 5.5kg. Please advise how to manage?