Vitamin D is important for baby's bone development, especially in our part of the world where we have little sunlight some months. This supplement helps to ensure our children are getting enough of this vitamin with the super easy dropper style bottle. You literally just need to let one drop drop onto your nipple or finger and then let baby suckle or lick for 30 seconds. As a breastfeeder I have literally just let one drop fall into my nipple pre feed safe in the knowledge that whilst he feeds he is getting what he needs from this supplement.