Who said "Laughter really is the best medicine."?

This quote is attributed to Butters Stotch.

Laughter really is the best medicine. - Butters Stotch

"Laughter really is the best medicine."

Butters Stotch Humor

"I'm not bad, I'm just drawn that way"

"Aw, hamburgers!"

"You're grounded, mister!"

"I have to go do my chores now"

"Never underestimate the power of a good laugh."

"Laughter is the best medicine."

"A good laugh is the best medicine."

"Laughter is contagious and wonderful."