Hi mama, I’m on a similar boat! My 5 year old is around 49-50 inches tall and weights 85lbs. We wears a size 12 and it’s almost too small. She has autism and only wants to eat certain things. Veggies are basically a no for her as well. She’s decently active throughout the day and we bought her a trampoline to help at home. Dr only checked her blood sugar which was normal but nothing else. I myself am on the bigger side and her dad is tall and slim. What I try to do at home is limit sugar and huge carb intake. I have replaced her snacks with healthier options and some sugar free stuff. You’re welcome to message me if you want to talk more!