A Utah State Prison inmate serving time on a burglary conviction was given an additional 1-to-15-year prison sentence Tuesday after pleading guilty to sexual abuse of a child.

Second District Judge Douglas L Cornaby sentenced Jeffrey T. Nelson, 22, to the additional prison term despite Nelson's plea that he was simply doing a friend a favor by letting two young girls stay in his Bountiful apartment last December.Nelson was on parole from the state prison when he allowed the 12- and 13-year-old girls and another friend to stay in his apartment. Nelson said he didn't know the girls were under 14, the legal age of consent, and thought they were older.

He was originally charged with two counts of rape of a child, both first-degree felonies that carry a prison term of five years to life and a minimum mandatory sentence of 5, 10 or 15 years, and one misdemeanor charge of supplying alcohol to a minor. Another first-degree felony charge, sodomy upon a child, was dismissed after a preliminary hearing in Bountiful 4th Circuit Court.

Nelson pleaded guilty in a plea negotiation with the Davis County attorney's office to a single charge of sexual abuse of a child, a second-degree felony.

Prosecutor Carvel Harward told Cornaby in a March 29 pretrial hearing that he anticipated problems with his two prime witnesses, the two girls involved.

The 12-year-old girl was a willing participant in a sexual encounter on Dec. 18 in Nelson's apartment, Harward told the judge, and testified only reluctantly at his preliminary hearing. The 13-year-old involved in the encounter the next night is a frequent runaway and can't be counted on to appear to testify, Harward said.

Nelson told the judge Tuesday he made a mistake but was simply doing a friend a favor by allowing the two girls to stay in his apartment over the Christmas holidays. He was working long hours and was gone most of the day, Nelson said, and the girls told him they were older than they are.

The judge said he recognized the girls were there voluntarily but said that did not change the fact they were only 12 and 13 years old and that Nelson, according to an Adult Probation and Parole report, was supplying them with alcohol and marijuana.