NORRISTOWN — A Michigan man already serving time in federal prison for manufacturing child pornography while engaging in text communications with a teenage Montgomery County girl admitted in county court that he met and sexually assaulted the girl at a Limerick Township hotel.

Mark Allen Hillis, 60, of Southgate, Mich., was sentenced in county court to 15 to 30 years in a state correctional facility after he pleaded guilty to charges of involuntary deviate sexual intercourse with a person under 16, unlawful contact with a minor and sexual abuse of children photographing and depicting sexual acts in connection with incidents that occurred in December 2019.

Hillis also must complete three years’ probation following parole, meaning he will be under court supervision on the county charges for 33 years.

The county sentence, imposed by Judge Thomas C. Branca as part of a plea agreement, will run concurrently with a 25-year federal sentence Hillis received in U.S. District Court in Philadelphia last November after he pleaded guilty there to charges of enticing a minor to engage in criminal sexual activity, traveling to engage in illicit sexual conduct, manufacturing and attempted manufacturing of child pornography, transferring obscene material to a minor, and possessing child pornography.

Under the federal and county sentences, Hillis won’t be eligible for parole until he’s in his 80s.

With the county charges, prosecutors essentially handled the charges related to Hillis’ hands-on contact with the underage girl at the Limerick hotel.

Assistant District Attorney Gabriella Glenning sought a significant state prison term against Hillis.

“The defendant fostered a relationship with a 13-year-old, built her trust, made her feel like they had a relationship and under that had her send him nude photographs of herself and then ultimately meeting up with her in person to accomplish his goal. That is heinous,” Glenning said. “To facilitate a hands-on offense is just horrendous.”

Prosecutors said the charges arose from Hillis’ sexual exploitation of the underage girl by using the internet and text messaging over a period of months, by traveling from…