Should my toddler take vitamin d?

Depends: Breastfed infants need vitamin d supplements, however once a child is eating solid food and drinking vitamin d fortified milk it is not necessary as they are probably getting the recommended 400iu of vitamin d. However some children with chronic diseases may need supplements in addition to their dietary intake.

Depends on diet: Most infants and children will get enough vitamin d from drinking infant formula or milk fortified with vitamin d as long as they are drinking at least 1000ml (about 32 ounces) each day or other foods fortified with vitamin d. Children who are exclusively breastfeeding or toddlers who aren't drinking much milk will also need vitamin d supplements.