4 month old twins, bigger twin falling being in weight. Advice?

Question by Mrs.Mommyx2: 4 month old twins, bigger twin falling being in weight. Advice?
My twins were born in January of this year at 36 weeks 1 day. Baby A weighed 4lbs 12oz while baby B weighed 4lbs 6oz. Now 15 and a half weeks later Baby B is well over 9lbs at yesterdays check up while Baby A is just hitting 8 1/2lbs. (They are Identical, and I know this because during my pregnancy I suffered with TTTS which is a rare disease of the placenta that only affects Identical twins and was told

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