If You Believe (1999)

Bah! Humbug! Susan Stone is definitely what you'd call a modern-day scrooge. She is a young, jaded book editor who is consumed with self-doubt and has lost the passion and drive that defined her childhood persona. On the verge of losing her job and being completely on the "outs" with her family, Susan has nearly given up on happiness. Out of nowhere, a cheerful, carefree seven-year-old girl named Suzie awaits Susan back at her apartment. It turns out that little Suzie is the embodiment of Susan's inner child, she is Susan as she once was years ago. Suzie has come to help the adult Susan rediscover and recapture the love of life that she's lost.