"Happy Face" is "inspired by a true story," according ... "Melissa had to reconcile the loving relationship she had with her father as a child with the monster her father was in reality.

"Happy Face" is "inspired by a true story," according ... "Melissa had to reconcile the loving relationship she had with her father as a child with the monster her father was in reality.

You might not know the full story behind the Dennis Quaid and Annaleigh Ashford-led series. Here's the disturbing truth ...