Grandpa!

Grandpa and Grandma were visiting the kids overnight, when Grandpa found a bottle of Viagra in his son's medicine cabinet. He asked the son about using one of the pills.

The son said, "I don't think you should take one; they're very strong and very expensive"

"How much?" asked Grandpa, "$10.00 a pill," answered the son.

"I don't care," said Grandpa, "I'd still like to try one, and I'll leave the money under your pillow as soon as I break this bill.

The next morning the son found $110.00 under his pillow. The son said, "I told you each pill was $10.00, not $110.00."

" I know, the hundred is from Grandma.