Longtime St. Paul police officer Jon Grahek never got to see what became of those accused of killing his 22-year-old son. Grahek died in January, four months before a judge sentenced a man involved in the slaying to 30 years in prison.

The Thursday sentencing of Noah Duane Baker, 20, of Duluth, offered Grahek's family "a degree of certainty and finality" over the February 2017 shooting, according to a news release from the St. Louis County Attorney's office.

Baker, who pleaded guilty to second-degree murder, is one of five people accused of involvement in the death of William Grahek, a student at the University of Minnesota Duluth who was shot inside his Duluth home during a robbery. Investigators say Baker and two others were trying to steal Grahek's bedroom safe.

Inside a Duluth courtroom Thursday, 23-year-old Tara Rai Baker, Baker's sister, was also sentenced to 57 months in prison after pleading guilty as an accomplice. Police say she drove the getaway car from the scene. But District Court Judge Mark Munger stayed her prison sentence for a period of six years probation.

She has been in custody for 15 months and will serve two more months in jail, in addition to other probation conditions.

Prosecutors Victoria Wanta and Jessica Fralich stressed in court that "no sentence will ever make up for the loss of Mr. Grahek," according to the county attorney's office.

William Grahek, of Centerville, graduated from Centennial High School and served in the U.S. Army Reserve. Jon Grahek, a St. Paul police sergeant, was diagnosed with cancer shortly after his son's murder and died Jan. 2.

Cases involving the three other suspects are pending.