GRAND HAVEN TOWNSHIP, Mich. — A Michigan mother who was fatally shot alongside her six children by her husband had previously accused him in online posts of having an affair with a younger intern, according to reports detailing the family’s troubled marriage.

Kristopher Karolkiewicz, 47, killed his wife, Amanda “Mandy” Karolkiewicz, 39, and their six children — ages 5 to 15 — at their home on Riverside Trail in Grand Haven Township on July 24, 2026, before setting multiple fires in the house and turning the gun on himself, the Ottawa County Sheriff’s Office said. Autopsies confirmed all eight family members died from gunshot wounds. The couple’s pets also perished in the incident, which authorities have classified as a murder-suicide.

First responders discovered the bodies Friday afternoon after reports of smoke coming from the residence. The children included four biological sons and two daughters adopted from China.

Mandy Karolkiewicz, a substitute teacher with Grand Haven Area Public Schools who previously worked in banking and insurance, had posted extensively on Reddit under the username MandyK1179 about the couple’s marital struggles. In posts from around 2024 on the “As One After Infidelity” subreddit, she described meeting Kristopher while she was an intern at a beverage company in 2008. He was divorced and older at the time. They married in August 2009.

She wrote that years later, after having several children, “he was cheating with the intern again — the same age I was when I was the intern.” Mandy described feeling “miserably,” catching him being “sneaky,” and pursuing marriage counseling after what she called an emotional affair. She admitted to pushing him during one confrontation, framing it as a fight-or-flight response, and expressed fear about leaving because of their children and her own trauma and anxious attachment.

In later posts she noted the couple was “in a much better place 4.5 years out” but still fighting to maintain a healthy relationship. She emphasized she was working through the issues for the sake of the family and was not filing for divorce.

Kristopher Karolkiewicz had worked as a vice president of sales and marketing at the American Heart Association; his employment ended earlier in July 2026. Friends and family have remembered Mandy as a devoted, positive mother and the children as active siblings who enjoyed boating, sports, and a recent heritage trip to China.

No suicide note was reported, and authorities have not publicly identified a specific motive beyond the investigation into the domestic circumstances. The case is one of several family annihilation incidents reported in the United States this year. Community members have organized support and memorial efforts for the victims.

Sources

• New York Post