"There's nothing more we can do." Jordyn's parents heard those devastating words in November 2009 and lost hope for their little girl who had been bravely fighting acute lymphoblastic leukemia, the most common form of childhood cancer, for seven years. Doctors told the family to go home and make memories with their daughter. She had only weeks to live.

As the holiday season approached, Jordyn's mom saw a commercial for St. Jude Children's Research Hospital. The spots featured St. ...