A wife who was murdered alongside her six children by her husband had accused him of having an affair with a younger intern in explosive Reddit posts, according to a report.

Kristopher Karolkiewicz, 47, fatally shot the children — aged 5 to 15 — and his wife, Amanda “Mandy” Karolkiewicz, 39, at their Grand Haven Township, Mich. home before setting it on fire and then turning the gun on himself, according to police.

Just two years ago, Mandy Karolkiewicz wrote on Reddit under the username MandyK1179, that she was “living in a Hallmark Movie” — but other posts offered a darker glimpse into her married life and husband’s alleged infidelity, the Detroit News reported.

Michigan woman Amanda “Mandy” Karolkiewicz, 39, shared troubling Reddit posts about her marriage in the years before the murder-suicide.

In one 2024 post seen by the outlet, she described how she first met her older husband while she was working as an intern.

“He was divorced and older than me … fast forward ten years and five kids, he was cheating with the intern again — the same age I was when I was the intern,” Karolkiewicz allegedly wrote.

“After about a year of self-loathing, I remember crying and looking at myself in the mirror and realizing how… it was that I was the one who was living so miserably because of what he did,” she claimed.

“I finally realized that I had been the only person who has ever showed up for myself my whole entire life.”

If it wasn’t for the children they shared, she wouldn’t have worked towards patching things up with her husband, she reportedly wrote.

“I kept telling myself, ‘I love my kids more than I hate my husband right now.’ They have no idea — I faked it ’till we made it. We’re in a much better place 4.5 years out, but it’s still a fight to stay in a healthy place.”

Karolkiewicz frequented the “As One After Infidelity” sub-Reddit  — a peer support group for reconciliation after cheating — and in one of her first posts said she was “terrified” at the prospect of leaving her husband, according to the outlet.

“We have six kids, so the idea of leaving is insanely terrifying,” she allegedly wrote. “He’s always had major red flags that I ignored due to my own trauma and anxious attachment.”

Law enforcement investigate the scene of a fatal house fire on Friday, July 24, 2026, in the in Grand Haven Township, Michigan.

Karolkiewicz had caught her husband being “sneaky” which resulted in the couple deciding to try marriage counseling, she claimed on the thread.

She also wrote about one incident in which she pushed her husband after learning about his “emotional” affair, according to the outlet.

“I don’t feel bad still,” she reportedly commented on the page in 2024. “He towers over me and destroyed me mentally. It felt like I was being assaulted and needed to fight back. I think it’s a fight or flight thing.”

The couple got married in Aug. 2009 after meeting at a beverage company in 2008, according to a parenting-focused blog that Mandy Karolkiewicz kept over a decade ago.

Karolkiewicz and her husband had been together for nearly 17 years when they and their children were found dead in the burning home at around noon on Friday, according to police.

The family’s pets also died, officials said.

Mandy Karolkiewicz was fatally shot alongside her 6 children before the house was set on fire.

The Ottawa County Sheriff’s Office announced Monday that autopsies determined all the family members died of gunshot wounds, and that Kristopher Karolkiewicz took his own life, labeling it a murder-suicide. Authorities added that multiple fires appear to have been intentionally set throughout the house after the killings.

The Sheriff’s Office and Ottawa County Medical Examiner did not immediately respond to The Post’s request for comment.

The couple welcomed their first child on April 25, 2011, which Mandy Karolkiewicz hailed as “the best day of my life (so far).”

Two more sons followed over the next four years, and the couple later adopted two daughters and had another biological son.

Kristopher Karolkiewicz worked as vice president of sales and marketing at the American Heart Association before his employment ended earlier this month.

Mandy Karolkiewicz was a substitute teacher in the Grand Haven Area Public Schools system after previously working in banking and insurance.

Source: https://nypost.com/2026/07/28/us-news/wife-murdered-alongside-6-kids-accused-killer-husband-of-affair-with-younger-intern-in-explosive-online-posts-report/