Hi my son is 2 years old his weight is 9 kg. is he healthy . we are desperately trying to feed him to help him gain weight . please guide .

What are his height: & bmi? Is his weight low for his height or does he have short stature? Has his pediatrician looked for genetic or other medical causes? Has his 3-day dietary intake been reviewed by a nutritionist? Has he had developmental screening, or assessment by early intervention? Are his head size & growth normal? Was birth wt. Normal? All these factors guide diagnostic evaluation & treatment.