Transcript for Grandma's Life Changing Idea Helps Her Grandson Use Hand
gift for two children who were already champions, but as you're about to see, the kindness of strangers and some modern technology are now allowing those boys to wave to us. Reporter: 3-year-old rayden Kahl, born without a hand, but still an all-star from the start, a Superman with his ukulele. He always hoped one day he might get a hand. A prosthetic that can cost the family thousands. His grandmother found an engineer from Georgia, willing to make it for free. Using 3D printing technology. It took him a month. No cost to the family. And that hand just arrived in the mail. All right, buddy! Reporter: Using his new fingers. This evening, waving to "World news tonight." He's back to school. It made us think of Alex Pring, who we have followed here. Born missing part of his right arm, perfectly happy to drive hitoy car anyway. But with the help of engineering students at the university of central Florida, he got his new arm. 3 D printing technology, again. They documented his first moments. Picking up that football. Good job, buddy. Reporter: The students determined to prove something. That you can build a prosthetic arm, without costing families tens of thousands of dollars. I hope people are upset. These arms shouldn't cost $40,000. Reporter: They built it for $350. And the first ting Alex did, was hug his mother with both arms. I lost it. I cried. Seeing all the things that he can do and, like, how happy he is -- that's -- that's a lot. Reporter: And tonight here, little Alex sending us this new video. Riding his bike. And who's just as excited? The family dogs, beans and burrito. Just trying to keep up with him
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