Viagra Joke

A father is visiting his adult son and sees a little blue pill on the table, and aske whats this?

The son replies its viagra.

Father says I have heard of that mind if I try it?

Son says sure but they are $10.00 each.

Father says Ill pay you tomorrow.

Next day father hands son $100.00.

Son says dad I said they were $10.00.

Father says I know the other $90.0 is from your mother