Who said "I believe in the power of persistence."?

This quote is attributed to Rex.

I believe in the power of persistence. - Rex

"I believe in the power of persistence."

Rex Perseverance

"I'm a dinosaur! RAWR!"

"Oh no, oh no, oh no, oh no, oh no!"

"I can't take the pressure!"

"Everything's gonna be okay, right?"

"Perseverance is the key to success."

"Don't give up on what you believe in."

"I've been through worse."

"You learn to live with the pain."