I don't remember exactly how much my kids weighed, but both were big and grew very fast. Audrey was always in the 95th percentile for weight until she started walking. Going by a growth chart that would have put her at about 17lbs at 6 months and about 20lbs 9 months. My son was off the charts for height and weight until his first birthday. Again, going off a growth chart he was around 20lbs at 6 months and 22 or 23lbs at 9 months. I know for sure that at 6 months he was wearing 12 month clothes and at 9 months he was wearing 18 month clothes. He's been in 2T since just before his birthday and now at 17 months he weighs about 27lbs. But, he's always been a monster.Keep in mind that all babies are different and they all grow and develop at different rates. Was your doctor concerned about his growth? If not, I wouldn't worry. Kids go through phases all the time and my daughter has been through plenty where she doesn't eat or drink much. (My son has never done that, although right now he won't eat meat, because his normal growth is like my daughter's growth spurts so he generally eats constantly. And his growth spurts were terrible, he'd be up every hour to eat.) Babies eat or drink when their bodies tell them to, so if your son isn't eating he probably just isn't hungry. Most of the time that's completely normal and again, if the doctor isn't concerned you shouldn't worry.The other thing about growth is that it doesn't always happen with height and weight at the same time. Has your son grown in height? At 9 months my daughter was in the 95th percentile for height and the 50th for weight. At her 12 month checkup she was in the 90th for height and the 50th for weight. She didn't gain much, if any weight but she sure got a lot taller.