Hi All.....This is an interesting topic.
I m a mother of 2 yr old and facing the same problem. Although my son was born with a handsome weight, he always looked lean. As he started growing, gaining height, he looked even more thin and had a small face. My husband has a broad body structure, my 8yr old daughter too was tooo chubby and healthy looking.Touch wood.
So i have to listen even more since everyone compares with papa or sis.
But the best suggestion i got ever since was from my mother when my son was only 10 months.She suggested me to give me all healthy and junk that comes his way. Let him taste chips, pepsi, maaza, ice creams, roti, curd and what not. We must apply our brain and give them wisely but dont ever restrict to few baby foods. In this way they develop taste for everything and once they feel hungry..they can eat whatever u offer them. and it worked for me. He now eats curd, chocolates roti rice and almost everything. He is still slim built only but is a active child. He does not look pale anymore.
and let them be happy .allow few chances to spoil ur home. paint the walls, tear the papers...throw the toys...reason...freedom...happiness...confidence....they move more....they feel more hungry and eat their full.
and yes ...best ans is " Doctors ke hisab se ye nilkul theek grow kar raha hai. he is active."
Thats my view.