A 7-year-old girl with a 3D-printed hand was selected to throw out the ceremonial first pitch at Game 4 of the World Series on Oct. 28.
Hailey Dawson was born with Poland Syndrome, a condition that resulted in a missing right pectoral muscle. She only has an undeveloped thumb and pinky on her right hand. Her mother, Yong Dawson, contacted UNLV’s Howard R. Hughes College of Engineering in 2014, after discovering that a typical prosthetic hand would run around $20,000 (and would need to be replaced every six months as Hailey grows up).
UNLV Engineering was able to produce a 3D-printed hand that allows Hailey to grab, grasp, grow, and throw things, and it only costs $5,000. The engineers tweaked the design as Hailey has grown, in order to manufacture more hands for her. UNLV is also using its fundraising page to get money to help more kids like Hailey, as well as veterans and others in need.

Image: UNLV
After receiving her new hand, Hailey, a baseball fan, was invited to throw out the ceremonial first pitch for the UNLV baseball team. Obviously enjoying the experience, Hailey asked her mother if she could possibly throw a pitch for her favorite team, the Baltimore Orioles, which she did in 2015.
Then came a request to throw out a pitch for the Washington Nationals, after Hailey met Bryce Harper in Las Vegas and asked him if she could visit the D.C. ball park.
Not stopping there, Hailey then expressed a wish to throw out the first pitch for all 30 Major League Baseball teams. Her mother helped spread the word through her Twitter account, @Haileys_Hand. Bleacher Report picked up the story, and soon nearly every MLB team replied on social media, offering to have Hailey toss the first pitch.
MLB did her one better, inviting her to toss the first pitch at Game 4 of the World Series between the Houston Astros and Los Angeles Dodgers. She received a special gold-colored World Series hand for the occasion, and got to spend time with some of the players.

Image: https://twitter.com/haileys_hand
Hailey has at least seven different hands, including the custom hands developed for the Orioles, Nationals, and World Series games. Part of the reason she goes through so many hands is because she likes to get them autographed by pro ballplayers. Her mother says that, in addition to promoting awareness of Poland Syndrome, the first pitch initiative has given Hailey a much-needed confidence boost.