Who said "Courage is being terrified but doing it anyway."?

This quote is attributed to Billy.

Courage is being terrified but doing it anyway. - Billy

"Courage is being terrified but doing it anyway."

Billy Courage

"I'm a big fan of science!"

"Mandy, wouldn't it be great if we could stay young forever?"

"I love the smell of destruction in the morning!"

"Why does everything have to be so complicated?"

"Never let fear stop you from chasing your dreams."

"Courage is being afraid but doing it anyway."

"Sometimes you gotta do what you gotta do."

"Sometimes you have to be the monster to stop the monsters."