Who said "Life's too short to be serious all the time."?

This quote is attributed to Bart Simpson.

Life's too short to be serious all the time. - Bart Simpson

"Life's too short to be serious all the time."

Bart Simpson Happiness

"Eat my shorts!"

"Ay caramba!"

"Don't have a cow, man."

"Cowabunga!"

"Babalú!"

"My greatest joy is making people smile."

"Laughter and love make a home."

"The best things in life are free."