"Texan Baby" joke

A Texan bought a round of drinks for all in the bar and
announced that his wife had just produced a typical Texas
baby, weighing a whopping twenty pounds.
"WOW!" was the response from everyone at the bar.
Two weeks later the Texan returned to the bar. The bartender
recognized him and asked, "Aren't you the father of the baby
that weighed twenty pounds at birth? How much does he weighnow?"
The proud father answered, "10 pounds."
The bartender said, "Why? I know that babies lose some
weight after birth, but ten pounds? He did weigh twenty
pounds, didn't he? What happened?
The proud Texas father said, "Just had him circumcised!"