Who said "I think that gratitude is the key to a contented life."?

This quote is attributed to Grace Kelly.

I think that gratitude is the key to a contented life. - Grace Kelly

"I think that gratitude is the key to a contented life."

Grace Kelly Gratitude

Actress American 1929–1982

"I like to think of myself as a fairly sensible, down-to-earth person."

"The important thing is your opinion about yourself."

"I really don't think I need blusher, I have these big ears."

"My life had been very sheltered and I hadn't seen much of the world."

"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"