The VD in the milk is just enough for you to take the Calcium in the milk. If you have additional Calcium source from food or pills then you need more VD. I used a kind of Mulivitamin liquid (Sorry I forget the name and vender. There's a baby face on the box, costs 16 - 19 dollars a box and can be found at shoppers drug mart) when my son was the same age. This kind of multiVitamin is just for babies.