EVERETT — A Snohomish County Superior Court judge has tacked more time onto a convicted murderer’s prison sentence.

Daniel Lyle Rinker is serving 28 years for shooting his girlfriend to death in 2014 during a dispute. While investigating the homicide Arlington police uncovered evidence that Rinker was having sex with an underage girl.

The abuse started in 2013 when the girl just 13. Rinker was 24 at the time.

Rinker, 27, pleaded guilty in February to second-degree child molestation and third-degree rape of a child. He faced nearly 10 years in prison.

Prosecutors agreed to recommend less time but insisted that Rinker only begin serving his sentence for his sex crimes after he’s finished his stint for murdering Jessica Jones, 25.

Judge Richard Okrent followed the recommendation Friday and sentenced Rinker to seven years in prison for abusing the teen.

Rinker was sentenced in February to nearly three decades in prison after pleading guilty to second-degree murder with a weapon.

Jones was shot to death April 8, 2014. Detectives quickly honed in on Rinker as the killer even though he claimed Jones was shot by someone in a passing car. Witnesses reported hearing an argument before the gunfire. They also spotted Rinker throw something into a nearby field. Police later recovered the murder weapon in the same location.

Rinker had threatened Jones in the past, and detectives also suspect that he was worried that the Tulalip woman was going to break off their relationship.

Doctors removed Jones from life support on April 9, 2014. She left behind a son.

During that investigation, Arlington police detective Mike Sargent discovered online conversations between Rinker and a girl, then 15.

The day after Rinker was arrested for murder police found the girl at his grandparents’ house. She was taken into protective custody. At first she denied any sexual contact with Rinker but later admitted that they’d had sex after Jones was killed.

Rinker spoke with the girl from jail and encouraged her to stay with his grandparents.

Detectives also reviewed recorded phone calls between the girl and Rinker when he was in jail in 2013. The girl, then 13, revealed that she might be pregnant. Rinker encouraged her to get an abortion and advised her to drink bleach.

He warned her that he would “go for a long time” if she gave birth.

Rinker will have to register as a sex offender once he’s released from prison.

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