Grandpa watched Tommy pull a worm out of the ground and told him that he would give him 10 bucks if he could put it back in.
Tommy left for a bit and said "Ok Grandpa, watch this". Tommy then pushed the worm right back down in the hole.
The Grandpa got out the 10 dollars and gave it to Tommy.
Tommy said "Grandpa I can't keep this because I cheated. I sprayed the worm with hair spray. That's why I was able to do that."
Grandpa said "No, you keep it."
The next morning at breakfast Grandpa walked up to Tommy and gave him another 10 bucks.
Tommy said "No Grandpa. You already paid me."
Grandpa replied "That money was from Grandma."