1 First of all, is the baby healthy? If it is healthy, there is no need to gain weight deliberately.

2 The child's health, not especially because of thinness, affects all indicators, and the doctor has not asked parents to make the baby fat.

3 The baby's diet needs a balanced nutrition, including vegetables and fruits, meat, eggs, poultry, milk, coarse grains, full but not full, regular diet, don't overeat, and don't eat too many high-calorie and high-sugar foods.