Any mummy care to share their preterm baby’s growth journey?

Hi mummy! I have 2 premature babies. A girl who is now 13 yrs old, gave birth to her @ 36 weeks gestational. She weighs 2.4kg when she was born but she wasn't hospitalised as she has no health issues and able to go home with me the next day. She picked up weight quite fast! I remember her as a chubby baby back then but as she grows up she is very petite today. Another preemie of mine is 4 mths old. He was born at 35w6d @ 2.79kg. My gynae & I were really surprised at his weight! He was in the NICU & Special Nursery Care together with me till the 5th day when we both got discharged from the hospital. I had an infection due to PPROM and he had to be on antibiotic during his stay but he was born healthy. He dropped a bit of weight when he was in the SNC and he also had jaundice. Underwent phototherapy there. He still dropped a bit of weight when I brought him home. My milk didn't come in when we got home so I fed him with fm. My milk only came the next day so I nursed him first before feeding him fm as what was adviced by his PD. Still doing the same today. His jaundice was also high back then and I fed him on demand. That way he can flush out the bilirubin. He picked up weight very fast and the nurses are often surprised when they took his weight. I've had 2 PDs who said that he's on the big side & chubby for his corrected age. Your premmie will gain weight very fast, trust me. Just feed on demand. Will definitely drop some weight for the first few weeks. Same with every babies.