Johnny goes to Grandpa and Grandma's house on Saturday and meets Grandpa in the front yard.

"Johnny, I'll give you $10 if you can put that worm back in it's hole"

Johnny thinks and runs inside and comes out with some hair spray, lays the worm straight and sprays it solid. He then sticks it back in the hole.

Grandpa pays off and Johnny goes home. The next day Johnny comes back and Grandpa gives him another $10.

"Grandpa, you already gave me $10"

"That's from Grandma"

Obviously before Viagra.