With adequate milk supply, calcium supplements are not needed before one year of age, but vitamin D supplements are needed to promote calcium absorption. Infants aged 0 to less than 6 months should be exclusively breastfed. Breast milk is the single best food for infants of this age to meet their calcium needs. Infants over 6 months of age should start to add complementary foods, and milk is a very important part of complementary foods. Infants should consume more than 600ml of milk per day (including breast milk or other milk products), which can satisfy their calcium needs. Regarding vitamin D, it is recommended to take vitamin D supplements from infancy to adolescence, at least 400 U/d. It is also recommended to sunbathe to promote vitamin D production (sunbathing can expose the face, arms, legs, and buttocks, but avoid direct sunlight to the eyes). It is recommended to monitor your baby’s growth and development, have regular medical checkups, and take nutritional supplements as prescribed by your doctor.