'You Are Killing My Mom': Pa. Mother's 2 Daughters Allegedly Witnessed Boyfriend Strangling Her

Thadius McGrath, 35, allegedly admitted to attacking Samantha Rementer "after she made him mad"

Photo: Samantha Rementer/Instagram

A Massachusetts man is behind bars after he allegedly strangled his girlfriend to death in front of her young children before attempting suicide.

According to the criminal complaint obtained by PEOPLE, Thadius McGrath, 35, murdered 31-year-old Samantha Rementer at her Holland, Penn., home on June 8.

He faces one count of first degree murder and one count of third degree murder in connection with Rementer's death.

Police allege in the complaint that during an interview with detectives with the Northampton Township Police and the Bucks County District Attorney's Office, McGrath admitted to first beating Rementer's face with a step ladder, and then a lamp, "after she made him mad."

He then allegedly wrapped the cord from the lamp around her neck and strangled her to death.

According to the complaint, McGrath allegedly said that Rementer's two daughters, ages 4 and 1, witnessed the killing, and that the 4-year-old said: "Please stop, please stop. You are killing my mom."

Citing Rementer's family, the Bucks County Courier Times reports McGrath was not the father of the two girls. Rementer shared them with her late partner, who died of a heart attack in February 2021.

Samantha Rementer/Instagram

McGrath allegedly first admitted to strangling Rementer during a phone call to his father, the complaint states.

Then, McGrath's mother, after a "possibly suicidal call" from her son, requested that police conduct a check on him at Rementer's home, according to the complaint.

Upon arrival and after "several unanswered knocks," law enforcement made their way into the home, where they encountered the 4-year-old.

She allegedly told police that McGrath had "killed mommy because she was annoying him," adding that McGrath shot himself accidentally.

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The 1-year-old was found still secured in her high-chair in the dining room, per the complaint.

Police found McGrath in a bedroom appearing to suffer from a self-inflicted gunshot wound to the mouth. A handgun was also discovered, nearby.

McGrath was transported to the hospital, where he survived.

In a news release, Bucks County District Attorney Matt Weintraub said, "This man murdered Ms. Rementer in front of her children. ... He will be made to pay an exacting price for his crimes."

In addition to the two murder charges, McGrath faces two counts of endangering the welfare of a child, one count of recklessly endangering another person and one count of possession of an instrument of crime.

McGrath is being held at the Bucks County Correctional Facility without bond.

It wasn't immediately clear if he entered pleas to the charges or retained an attorney to comment on his behalf.

If you are experiencing domestic violence, call the National Domestic Violence Hotline at 1-800-799-7233, or go to thehotline.org. All calls are toll-free and confidential. The hotline is available 24/7 in more than 170 languages.