A Pennsylvania woman, her boyfriend, and another man have been arrested and charged with the murder of her 71-year-old mother.

Melissa Beacom, 49; Matthew Bates, 18; and Robert Jack, 18, face charges of criminal homicide, conspiracy to commit criminal homicide, abuse of a corpse, and tampering with physical evidence, according to the Westmoreland County District Attorney’s Office. Beacom also faces charges of criminal solicitation.

Bates, Beacom’s boyfriend, told detectives that Beacom and her mother had a difficult relationship because of custody issues surround Beacom’s son, who requires around-the-clock care.  The Westmoreland County Cour granted custody of the boy and a daughter to her parents, TribLive.com reported.

Bates said he was at Robson’s home on December 11 working on a car and that he and Beacom later left and returned, meeting up with Jack, the district attorney’s office said. At that point, Beacom asked the two of them to kill Robson, so they went inside and shot her to death. Then they put her body in a crawl space beneath the back porch and tried to clean the blood from the living room.

Police were notified Robson was missing two days later when a school principal said home health care workers found Beacom’s son at the home alone. The next day, police searched the property with bloodhounds and found the body, along with the poorly cleaned up blood stains in the living room.

It’s not clear where Robson’s husband, Edwin Robson, was at the time of the murder or the days afterward. He told TribLive.com that his wife’s death was a “shock” and declined further comment.

All three suspects are being held without bond and are due in court on December 28.

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[Featured image: Alice Robson/Stuart Funeral Homes]