Isaac Smith thought killing his pregnant lover would erase his secret. Instead, it cost him every remaining day of his life.
She had texted him about the gender-reveal party. She was five months along. She was excited.
Two days later, she was dead — shot in the head in her own yard by the man she believed was her baby’s father.
Isaac Smith, 30, of Pennsylvania, has been sentenced to life in prison without any chance of parole after being convicted of first-degree murder in the killing of 26-year-old Karli Short. A jury also found him guilty of the first-degree murder of her unborn child. He will die behind bars.
The Morning Everything Ended
On September 13, 2021, Karli was at her home on Furnace Alley in McKeesport — a small city roughly 12 miles outside Pittsburgh — when her uncle heard her on the phone.
“Are you coming to the front or the back?” she asked the caller.
She walked outside. A single gunshot followed.
Karli had been lured into her own yard and executed. Prosecutors say the man on the other end of that call was Isaac Smith.
A Double Life, A Deadly Decision
Smith had been seeing Karli on and off, though he later downplayed the relationship as casual. But Karli believed the child was his — and she made no secret of it. She had been texting him about the pregnancy, asking for financial support, and planning a gender-reveal celebration just two days before her death.
Smith, however, had moved on. He had a new girlfriend. She had already met his parents — just days before the shooting.
According to Allegheny County Deputy District Attorney Ryan Kiray, Smith had a crystal-clear motive: “The walls were closing in,” and he “did not want the double life he was living to be exposed.”
In a cruel twist, Smith was not even the father. He murdered a woman and her unborn baby over a secret that was never his to begin with.
His Own Words Condemned Him
Hours after the killing, Smith walked into Allegheny County Police headquarters and sat through a three-hour interview — claiming he wanted to clear his name. He even told detectives he was willing to be present in the child’s life.
Investigators initially believed him. Then they kept digging.
The new girlfriend. The family introduction. The timeline. It all pointed to one man with every reason to silence Karli before his two worlds collided.
‘A Murdering Crowded’
At sentencing, Karli’s father faced Smith directly and delivered words that silenced the courtroom.
“My grandchild was not murdered by her father,” Brandon Short said. “Her father did not kill her. A murdering coward did.”
Karli’s aunt described a young woman who was glowing with excitement over the baby she would never get to hold. “That was her joy; that was her moment,” she said — then turned toward Smith and added that sharing a room with him was “devastating” and “unimaginable.”
What Happens Next
Isaac Smith will spend the rest of his natural life inside a Pennsylvania prison. There is no parole. There is no second chance. The gender-reveal party that Karli had been counting down to never happened. The baby was never born.
Two lives were taken that morning in McKeesport. One man made that choice — and a judge made sure he’ll spend eternity answering for it.
