it helps baby to grow up and be strong when he/she will grow up......
the secretion of breast milk in men, or in women who are not breastfeeding an infant.
Of course it does. It helps to develop milk secreting glands.
In mammals, it's called lactation.
Breast milk is a secretion and you do not get the infection through the breast milk. Though this can happen rarely. As anything is possible in biology.