Robert Vrablik was on the Twilight trail with his sister and a friend when he fell and landed on his face and chest around 3 p.m. Saturday, New York State Police said.
Vrablik was responsive while being taken to Albany Medical Center but declared dead at 7:18 p.m., police said.
Cardiac contusion was the cause of death, the DailyFreeman reports.
Vrablik was a Florham Park volunteer firefighter and was applying for positions as a law enforcement officer, his obituary said.
"Rob embodied endless goodness and capacity to bring happiness to others," the obit reads. "He was a kind, charismatic, exuberant, and amazing young man."
Vrablik attended Seton Hall Preparatory School and later graduated from Penn State with a degree in criminology.
He was a member of the university's Kappa Sigma fraternity, which expressed condolences on Facebook.
"Rob was the most selfless person and became a friend to everyone he met," the post says. "Our thoughts and prayers go out to the Vrablik family. Rest easy Rob, we love you and you will be missed dearly. AEKDB."
Visitation is scheduled for Thursday, March 14 from 4 p.m. to 8 p.m. at Leonardis Memorial Home in Florham Park.
A Mass of Christian burial will be at 10 a.m. Friday, March 15 at Holy Family Church. Interment to follow at Gate of Heaven Cemetery.
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