Girl with 3D prosthetic hand throws first pitch at World Series

A young girl with a 3D prosthetic hand threw out the ceremonial first pitch at Game 4 of the World Series.

7-year-old Hailey Dawson is on a mission to throw the first pitch for every Major League Baseball team. Last night, she crossed the third off her list.

The Houston Astros welcomed the young fan to the park to throw out the first pitch before Game 4. She got to throw the pitch with a custom World Series hand, too!

Hailey has already thrown a ptich for the Orioles and Nationals, and has invitations from the 27 other MLB teams.

Hailey was born with Poland Syndrome, a birth defect that limited her right hand to a palm, pinky, and thumb with only cartilage, no bone. She has no middle fingers and is also missing the pectoral muscle on her right side.

But with the help of students from the College of Engineering at the University of Nevada, Las Vegas, Hailey now sports a functional hand that operates on wrist movement. Moving her wrist down allows her to grasp objects and moving it up opens the hand - which lets her throw a baseball.

"Her favorite thing to do with her robotic hand is throw first pitches," said her mom, Yong Dawson, "It touches my heart every time I watch my daughter do something that makes her happy."

To follow Hailey's story and tour, visit her Twitter account @Haileys_hand.