my baby 1 year 9 month old she is having thyroid since birth but her weight is 8.7 kg she cannot eat proper diet is her weight is less as per her age

A. Giving thyroid medication on a daily basis, will help with maintenance of that but you have to give high-protein diet on a daily basis for the child to gain weight. A few babies are thin by birth and genetics, and you cannot force them to become chubby in such a case