EVERETT — She was 11 when her dad was gunned down near Lake Stickney.

It’s hard to put into words all that was taken from her and her younger siblings that day on June 9, 2005.

“I lost a whole childhood. I can’t get that back,” the woman, now 22, said Thursday.

She last saw her dad, Jessie Williams, when he dropped her and her 7-year-old brother off at school. He didn’t show up that afternoon to pick them up.

“My last memory of my dad was the night before he was killed. He was sitting on the side of the tub while I was taking a bath and playing action figures with me. He was good at making the sound effects the way I liked to. He got me ready for bed and told me he loved me,” Williams’s son, now 18, wrote in a letter.

The man who killed Williams was sentenced Thursday to 8½ years in prison. Bunthoeum Nem, 38, had pleaded guilty earlier this year to first-degree manslaughter.

Snohomish County Superior Court Judge Bruce Weiss said he believes Nem is remorseful for his actions. He also believes the defendant deserved the maximum sentence allowed by law. He may be a different man than he was the day he shot Williams but he waited 11 years to do the right thing.

“You could have come forward and helped start the healing process earlier,” Weiss said.

An emotional Nem apologized to Williams’s family, saying he wishes he would have made different decisions back then.

Detectives believe Nem and two others, Youthy Chim and Saravouth Sun, planned to rob Williams during a drug deal.

A witness told police that he drove Williams to Snohomish County to buy marijuana. They met three men at an Everett McDonald’s and followed them to the boat launch at Lake Stickney, Snohomish County deputy prosecutor Matt Hunter wrote in court papers.

Nem approached their vehicle, threw a duffle bag through a passenger window and began firing. Williams was struck in the chest. His buddy drove him to a local hospital. Williams died there.

The friend lied to deputies investigating the case in 2005. He told them he and Williams were in the area to buy a car. He eventually was interviewed again and was “more truthful,” Hunter wrote.

Yet he refused to cooperate with investigators further, declining to look at a photo lineup of suspects. Some speculated that he took the slain man’s drug money, according to court papers.

In 2005, detectives pursued leads and gathered evidence, but the investigation grew stale. The case detective retired in 2007, and the homicide was turned over to the Snohomish County Sheriff’s Office Cold Case Unit.

A break in the investigation came last year, when Chim, identified as a suspect early on, admitted that he and two others went to the area to sell marijuana. He told police that Nem shot Williams during the encounter.

Nem and Chim were arrested in June for investigation of first-degree murder. Sun is behind bars in a federal prison on an unrelated case. After their arrest Nem and Chim declined to speak to detectives.

Hunter on Thursday explained that the arrest “was the last pin to pull” in an investigation that lacked strong, admissible evidence. Detectives had hoped that at least one of the suspects would cooperate.

“There was a reason the case was not cracked 11 years ago,” Hunter said.

The case didn’t get much stronger after the arrests. Prosecutors were left with a tough decision: go to trial on a shaky case or strike a deal with Nem and guarantee he spend some time in prison.

“To be candid, the state’s case against Mr. Nem was weak and my recommendation was that the case should go to trial,” Snohomish County public defender Natalie Tarantino wrote in court papers. “At an early meeting, Mr. Nem informed me that he could not and would not contest his responsibility for Mr. Williams’s death.”

Prosecutors agreed to reduce his murder charge to manslaughter. In turn, Nem agreed to cooperate with investigators and testify against the other two defendants. Chim remains charged with first-degree murder. Sun has not yet been charged.

Through Nem’s cooperation detectives learned that Chim and Sun were allegedly more involved in the robbery than investigators were originally told. Sun allegedly provided guns to Nem and Chim and was also armed, the judge was told. All three planned the robbery, Hunter said.

Detectives have a stronger case against the other two suspects, including Sun, who was involved in other crimes.

Nem was the only person who knew Williams. The two had met not long before the robbery. He told police that he panicked during the heist, believing that Williams was reaching for a gun. He shot him and fled without the money.

“Mr. Nem separated from his friends and old life after that day and rarely saw them again. He thought the police would be coming for him year after year, but they did not,” Tarantino wrote.

“When he was caught 11 years later, he appeared to genuinely feel some relief,” she added.

Kellie Bendickson also has found some relief after so many years of not knowing what happened to her friend and the father of her two children.

“We never thought we’d get to this day,” she said Thursday. “We’ve tried to find healing. There have been all these unanswered questions.”

She thanked the cold case detectives Joe Dunn and Jim Scharf for never giving up on the case.

Nem’s conviction is another solve for the sheriff’s cold case team.

The unit was launched in 2005. It has identified more than 60 cold cases dating back to 1962. Many of the unsolved cases are from the 1970s to early 1990s when the sheriff’s office only had two homicide detectives.

About a year after the team formed, they were able to help solve the 2001 murder of Michael “Santa” Walsh.

Then they created the state’s first deck of cold case playing cards in 2008. Williams was featured on the 10 of Clubs. The cards feature unsolved cases dating back to the 1970s. The decks are handed out in prisons and jails.

The cards paid off in March 2010 when detectives chased after a tip on the 1979 murder of Susan Schwarz. Her killer was convicted and sentenced to 24 years in prison not long after. The team’s investigation also led to the conviction of Danny Giles, the man accused of killing Patti Berry in 1995.

“The families of homicide victims deserve to know how and why their loved one died — no matter how much time has passed,” Sheriff Ty Trenary said. “I’m proud of our cold case detectives’ commitment and passion to ensuring justice is served. Often, they are a victim’s only advocate.”

Williams attended college in Minnesota but struggled to find work once he was out, Bendickson said. He had a lot of people counting on him, including his three children. He wanted to do right by his family and felt pressure to provide. Williams sold marijuana, but “he didn’t live a life of crime,” Bendickson said.

He was a dedicated father, who attended his children’s medical appointments and school events and chaperoned school field trips. He was a loving man, who seemed to make friends wherever he went, Bendickson said.

He taught his children to value their education and strive for good grades. His son excelled in school and is in his first year of college.

“I imagine him bringing me out to college and I wonder if he would be proud of me or what kind of advice he would give me,” the teen wrote. “I believe I turned out to be a pretty good kid but to think of how much better my life would be if I had my dad, still hurts.”

His children also have his sense of compassion, Bendickson said. Even now, she imagines him explaining to her how people can make mistakes, learn from them and change. It is a lesson that he must have passed along to his oldest daughter.

“I do want (Nem) to know I personally forgive him,” the young woman said Thursday. “I know it’s the only way I can keep going.”

Diana Hefley: 425-339-3463; hefley@heraldnet.com.