The young lady entered the doctor's office carrying an infant.

"Doctor," she explained, "the baby seems to be ailing. Instead of gaining weight, he lost three ounces this week."

The medic examined the child and then started to squeeze the lady's breasts.

He then unbuttoned her blouse, removed the bra and began powerfully sucking on one nipple.

"Young lady," he finally announced, "no wonder the baby is losing weight, you haven't any milk!"

"Of course not!" she shrieked. "It's not my child, it's my sister's!"