Phelan grew up in Greenlawn in Suffolk County and his teachers in the Harborfields School District described him as a standout human being.
"Kind of what we call our old school kid, he thanked you after every class," Kerri McGinty said.
"We're just gonna miss him deeply. He's just somebody that should be on this planet," Susan Turrini said.
Phelan showed talent and work ethic from an early age which led him to signing a contract with the Phillies straight out of high school.
He was a promising pitching prospect who could throw a fastball 90+ miles per hour and had last pitched in the minor leagues in 2021.
On April 14, Phelan was preparing for the upcoming season at the team's spring training facility in Florida when he collapsed in the shower.
"I got a CAT scan on my brain and that was fine and then I got a CAT scan on my chest and they told me that I had a nine-inch mass in my chest," Phelan told our sister station WPVI back in June.
Initially doctors believed it was non-Hodgkin's lymphoma, but as treatment failed they soon realized it was a more rare and aggressive cancer called T-cell Acute Lymphoblastic Leukemia (T-ALL).
"Anytime we heard him talking to anybody on the phone, he would say, 'I'm worried about my mom and dad.' He was worried about us, and he was just suffering," Phelan's father, Chris, said.
A funeral will be held for Phelan this week.
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