How big was/is your LO at 18 months?
My son was a little over 8 weeks early. He was 3lb 10 oz when he was born and is now 18 lb 3 oz at 18 months (16 adjusted)
Dr said she's not worried because he's still following his own growth curve and hasn't dipped at all on his chart.
It's just weird to have him be so tiny lol
Mine was a 29 weeker, she was 2lbs 15ounces at birth and now at 10.5 months (8 months corrected) she is almost 17lbs. She's still small but she babbles, crawls, pulls herself up, cruises furniture, tries to walk, feeds herself (with her hands).. everything a full term 10-12 month would be doing. I often wonder where my itty bitty prem went lol, they grow so fast, even the tiny ones.
Sorry, I also meant to mention.. my full term daughter, weighed 22lbs at 18 months, so I think 18-19 pounds for a 16 month old is probably just fine. If the doctor isn't concerned, I wouldn't worry too much about it as long as he's eating well.
My little guy was born 9 weeks early and was 4lbs. He's 18 months now and just over 20 lbs. he eats everything, but is super active. We give him pedisure everyday and he's gained some good weight. He's only in the 3 rd percentile right now.