It is very important to the baby's brain. If the baby is lack of it, he/she may be do not want to eat because they do not have enought brain energy to stand the noise or sent too much message to the brain. And they may be cannot sleep and also be naughty and easy to get angry.
It is important to the grow of brain because it help to transter oxygen and nutrient to the it through the blood vessels. And also, if people was frighten, some harmful material will be producen, vitamin C can stop the harmful material to produce because of our frightening.
It is important to the bone to grow, and especially 4~5 years old children they need 4 times vitamin D as much as adult. The grow of the skull is grow according to the grow of brain, so it is very important.