"Good Baby" joke

A three-year-old walked up to a pregnant lady while waiting with his mother in the doctor's office...

He asked the lady, "Why is your tummy so big?"

She smiled and replied, "I'm having a baby."

With big eyes, he asked, "Is the baby in your tummy?"

She answered, "He sure is."

Then the little boy, with a puzzled look, asked, "Is it a good baby?"

She said, "Oh, yes. It's a real good baby."

With an even more surprised and shocked look, he asked, "Then why did you eat him?"