The Faithful(2007)

Friendship takes more than a wish.

On his thirteenth birthday, Kevin wishes that his dog, Danny, could be a real friend to him. Upon waking up the next morning, he finds that his furry friend has actually become human! Thanks to Danny's dog-like characteristics, he is able to become exceptionally popular in school and brings Kevin up with him. But when the girl of Kevin's dreams, Mary, falls for Danny ...