A boy who was 15 when he killed a father walking a dog in Overbrook last year sat with his head buried in his arms as his victim's widow testified during an emotional hearing Thursday in Common Pleas Court.

Tyfine Hamilton, now 17, was sentenced at the hearing to 25 to 80 years in state prison. He pleaded guilty last week to third-degree murder, robbery, and related offenses in the death of James Stuhlman, 51, co-owner of a Media landscape-supply firm.

"There's not much to say - I took a special man from you and I'm sorry," Hamilton told Stuhlman's widow, Theresa. "I shouldn't have been out there that night, and I shouldn't have had a gun."

According to police, Hamilton and two other boys - Brandon Smith, then 15, and an unidentified 14-year-old - had just finished a game of basketball around 8:30 p.m. on March 12, 2015, when they decided to search for someone to rob, and came upon Stuhlman walking his dog in the 6400 block of Woodcrest Avenue.

Stuhlman pleaded for his life, but Hamilton shot him once in the chest and the boys left him for dead, taking nothing, police said.

Theresa Stuhlman said that was the moment that her life and that of the couple's daughter, Elaina, then 11, changed forever.

"We were previously an equilateral triangle. We were a symbol of strength. You see, no matter how much pressure you put on any of its sides, a triangle is impossible to break," she testified Thursday.

"Now one whole side of the triangle is gone. We lost an entire dimension of our lives. Now Elaina and I are just two lines that don't have a third side."

Hamilton's attorney, Timothy Tarpey, said his client's "whole life has been filled with horrific abuse - physical and sexual."

In apologizing to Stuhlman's family, Hamilton said he would pray that Elaina, now 13, will "make it through life successfully."

Theresa Stuhlman noted that the person who killed her husband was not much older than her daughter is now.

"Kids with such little life experience ended a remarkable person's vibrant life in a city he absolutely loved," she said.

"What does this say about their lives, their parents, their sense of right and wrong, their education, and our society?"

The victim's sister, Suzanne Stuhlman, described the lasting impact of his death on everyone he touched, from coworkers and neighbors to students at his daughter's school.

"It was like a bomb was dropped on our lives," she testified. "Our personal 9/11."

Theresa Stuhlman said the slaying had compromised her sense of security and changed her outlook on life.

"To this day, I cannot walk down the street where my husband lost his life," she said.

Following Hamilton's sentencing, Smith's attorney, Joshua E. Scarpello, said his client had declined a negotiated plea offer from the District Attorney's Office and would take his case to trial.

The 14-year-old was charged as a juvenile and his case was heard in Juvenile Court.

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