The fiancé of an Ohio art student who went missing nearly 13 years ago was sentenced Thursday to three years in prison.

John Carter, 36, was charged with two counts of murder when he was arrested in March 2023. He eventually pleaded guilty last month to involuntary manslaughter as part of a plea deal.

The charges stemmed from the August 2011 disappearance of Katelyn Markham, who was last seen at her home in Fairfield, Ohio. At the time, Markham was a few weeks away from finishing her graphic arts degree at the Art Institute of Ohio—Cincinnati, and Carter had said they were planning to move to Colorado later that year.

Skeletal remains identified as Markham's were found in 2013 in a wooded area in Cedar Grove, Indiana, about 20 miles west of her home in Fairfield. Authorities ruled her death a homicide but did not determine how she was killed.

Butler County prosecutors have said Carter caused Markham's death by "physical violence and by force." They said Thursday that Carter still hasn't explained how or why he killed Markham.

Dave Markham, Katelyn Markham's father, read a letter in court before Carter was sentenced.

"Not a day goes by that I don't think of Katelyn," he said, imploring Judge Daniel Haughey to sentence Carter to the maximum sentence by law. "Let him feel the pain that many of us have endured for the past 13 years."

Carter did not speak during the sentencing hearing. His attorneys asked Haughey to impose probation or a minimal prison term, asking him to consider the law and not emotional statements.

Haughey, though, imposed the maximum term allowed under the plea deal, saying Carter "has shown no genuine remorse for this offense." He also noted that Carter did not try to help Markham or acknowledge what happened to her immediately after her death.

Markham's father previously told CBS News affiliate WHIO that Carter "stole a lot" from his daughter and her loved ones. 

"I often wonder what she'd be doing with her art and her career, and I think she would just be just an amazing woman," he told the station in March 2023. "And it does make me a little angry that he lived for 12 years scot-free thinking he got away with it. And a lot of us have missed Katelyn tremendously every day for 12 years. And it's not fair, and it's not right. And hopefully, it's going to be made right."

In:
• Homicide
• Indictment
• Ohio
• Crime