The Kid (2000)

Powerful businessman Russ Duritz is self-absorbed and immersed in his work. But by the magic of the moon, he meets Rusty, a chubby, charming 8-year-old version of himself who can’t believe he could turn out so badly with no life and no dog. With Rusty’s help, Russ is able to reconcile the person he used to dream of being with the man he’s actually become.