Preemie toddler that won't gain weight

Hi, guys.My son is a 26 MO who was born at 29 weeks and 2 days gestation. He has been stuck at about 20, 21 lbs. for what seems like forever. I offer him a variety of foods, lots of carbs and protein but he is super picky about what he eats. His list of what he consistently eats is growing shorter every week. He is not tongue tied. We thought his issue might be GERD, but the medicine that we've been giving him for the last couple of months only made a small, short-term improvement. He's been on two Carnation Instant breakfast drinks a day, which he drinks faithfully but they don't seem to be making a huge difference, if any. We're starting OT this coming Wednesday to see if the therapist has any ideas.I'm scared and frustrated. Do I give him cereal and PB&J sandwiches and pancakes for every meal? I'm at a complete loss. via /r/Parenting https://ift.tt/3gkuity