What my 5- and 7-year
old daughters call
breasts. They witnessed their little
twin brothers breastfeed, and therefore have no doubt as to the function of mammary glands on a human.
Mommy, look -- my dolly is having some of my milkies. (her
shirt is up and the
doll is "nursing.")
This is not "sick" -- it is a healthy
thing that the daughters are learning what to do when they have a baby.