Custer was asked to choose a celebrity guest to escort her to Akron Children's Hospital's "A Prom to Remember" event in March. Back then, she told ABC affiliate WEWS, the point guard was not as well-known. Custer is a point guard herself, so Dellavedova was a natural choice.
The teen was diagnosed with acute lymphoblastic leukemia in June 2014. She said the prom served as a break from everything she's been through.
"That night kind of took me away from what was really going on, getting treatments and stuff," she said. "It made me feel like a normal person."
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Custer said that she and Dellavedova have kept in touch since the prom, and she wishes him good luck before every game.
@jackie_custer16 great to meet you Jackie! Glad you had fun 👍— Matthew Dellavedova (@matthewdelly) April 2, 2015
Her date even invited her to an NBA playoff game, WEWS reports.
Custer said the attention Dellavedova has gotten for his performance in the playoffs just makes the memory sweeter.
"It actually makes me feel really big, like a superstar because he's so famous now," she said. "So when I talk to him I'm freaking out."
The teen said she's still in awe of how great of a night it was.
"Going to prom with Delly was a night I'll never forget," she told WEWS. "It was definitely magical, and he's the sweetest guy I've ever met."