Who said "I'm grateful for every person who believed in me."?

This quote is attributed to George McFly.

I'm grateful for every person who believed in me. - George McFly

"I'm grateful for every person who believed in me."

George McFly Gratitude

"I'm your density. I mean, your destiny."

"This is heavy."

"There's that word again, 'heavy.' Is there something wrong with the Earth's gravitational pull?"

"I'm not very good at science."

"Gratitude makes life richer."

"A grateful heart is a happy heart."

"Respect those who came before us."

"Life's greatest treasures are the people we love"