When you haven't breastfeed your baby the entirety of their infancy the breast milk dries up. The mother can no longer breastfeed their baby because their body

When you haven't breastfeed your baby the entirety of their infancy the breast milk dries up. The mother can no longer breastfeed their baby because their body thinks that their baby is all grown up (or dead) because it hasn't been drinking the milk. You can't just choose to breastfeed on a dime like that, you have to breastfeed from the beginning and continue on to keep up the milk supply. This is of course assuming you have sufficient capacity in the breasts to keep the baby alive in the first place, something not all women have these days.