MOUNT VERNON — A Sedro-Woolley man pleaded guilty Friday to first-degree manslaughter for the July 21 shooting death of his girlfriend’s 4-year-old son.

Trevor Braymiller, 25, was sentenced to almost eight years in prison — almost twice as long as Dwayne Kerrigan was alive. The child accidentally shot himself with Braymiller’s gun, prosecutors said.

About 15 members of Dwayne’s family were in the Skagit County Superior courtroom, at least one wearing a T-shirt with the child’s name and face on it. They cried and held each other after Judge Dave Needy handed down the 95-month sentence.

“It’s a very difficult case for all the family to deal with,” senior deputy prosecutor Trisha Johnson said.

After the shooting, which took place in the family home, Braymiller took the gun and fled to Big Lake. Hours later, a State Patrol dog found the gun at a church near the house.

Braymiller surrendered to police the next day, after an autopsy determined the boy had shot himself in the head.

In court Friday, defense lawyer Keith Tyne called the case “utterly heartbreaking … the saddest kind of case I can think of.” His client is overcome with remorse and never meant to hurt anyone, he said.

“Mr. Braymiller made very bad decisions in the days before this tragedy,” he said.

Although Tyne advised him to go to trial, calling the manslaughter case “defensible,” Braymiller refused to force Dwayne’s family to relive the trauma of the boy’s death during a trial, Tyne said.

Braymiller had been with Dwayne’s mother, Heather Brittain, for 3½ years and was a father figure to Dwayne, Tyne said. He and Brittain have a daughter together, who was also in the house during the shooting.

The manslaughter conviction is Braymiller’s first strike under Washington’s three-strikes law for serious offenses. His only other criminal history is drug-related: possession of marijuana with intent to deliver and possession of methamphetamine. He was on probation for that case when the shooting occurred and was not allowed to have the gun, which turned out to have been stolen.

The guilty plea to manslaughter dropped the two other counts against Braymiller: unlawful possession of a firearm and possession of a stolen firearm.

Needy ruled that drug addiction contributed to what had happened, which will allow Braymiller to seek chemical-dependency treatment in prison. After his release, Braymiller must serve three years in community custody. He also must pay $6,339 in restitution, mostly to cover Dwayne’s funeral costs.

In victim-impact statements, some members of Dwayne’s family said Braymiller should not get any “breaks.” Needy said that although the 95-month manslaughter sentence is at the low end for someone with Braymiller’s criminal history, he doesn’t see it as a break because Braymiller will have to live with what happened for the rest of his life.