My son is of 5 yr 3 month. His height is 125 cm and weighs 17 .7 kg. He appears very thin in appearance and fall sick every week. What should I do

A. weight n height is normal. give immunity booster food like-Eggs, youghrt, spinach, nuts like almond, wallnut, sunflower seeds, apple, and all seasonal fruits and vegetables and , oats, garlic, carrot, broccoli, butter, beans , mint juice, milk and milk products..