The children of Michele MacNeill helped get their father convicted of murdering their mother.
It was the children of Michele MacNeill who ultimately campaigned for an investigation into their mother's death, which they said was actually a murder perpetrated by their father.
They were right. But it took six years for Martin MacNeill to ultimately be convicted of killing Michele, and during that period, many secrets were uncovered about him.
Friday's "20/20" examines some of those secrets and looks back at how a seemingly happy family with eight children living in Utah was anything but.
Michele was a good student, a good athlete and loved playing the violin, her sister tells ABC News. She met Martin when she was just 21, at a Mormon gathering for singles. They soon eloped.
She gave birth to four children in five years. "Her family was her life," daughter Alexis Somers said. The couple adopted four additional children, including three from Ukraine.
Martin, a doctor and a lawyer, began to change after his 50th birthday. "He started acting very strangely. He became just very obsessed with losing weight and his appearance," said daughter Rachel MacNeill.
Her mother suspected Martin was having an affair and confronted him, Rachel said. He denied it, telling Michele she should improve her appearance. He suggested a full facelift, Rachel said.
Martin sent his wife to a plastic surgeon of his choosing and prescribed a list of strong drugs for her to take following surgery. They included Valium, Ambien and Percocet, she said.
The surgery took place on April 3, 2007.
Afterward, Alexis said, her mother looked awful and was "in a lot of pain." She suspected her father of doping up her mother and told him she would take over giving meds to her mom, she said.
Michele, who had bandages over her eyes following surgery, told Alexis to place the medicines in her hands so she could memorize them with her fingers, the daughter recollected. "'Give me each of the pills so I can feel it with my fingers, so if he tries to give me something else, I'll know what he's giving me,'" Alexis said her mother told her.
One week later, Michele was dead. Her body was found in the bathtub.
"'Your mom, she's in the tub. She's not breathing. I've called an ambulance,''' Alexis said her dad told her over the phone. "And then he hung up. ... He killed her. That was my first instinct."
An autopsy concluded she died from cardiovascular disease. Her children were skeptical.
At their mother's funeral, a woman named Gypsy Jillian Willis showed up. Their father would later hire her as a nanny. But Alexis knew that name from earlier conversations with her mother, who said she had found numerous phone calls on her husband's cellphone to Gypsy Jillian Willis.
"I moved in to help with the kids," Willis told ABC News. "When we had opportunity, I still slept with him."
Meanwhile, the couple's adult children pestered authorities to investigate their mother's death. Ultimately, two investigators with the Utah County Attorney's Office were assigned to investigate Michele's death.
They discovered Martin's medical career was based on two falsified transcripts that got him into medical school. He had been discharged from the military after claiming he was schizophrenic and hearing voices.
He had been convicted of forgery and grand theft, and served 180 days in jail after marrying Michele, the investigators discovered.
After convincing the state coroner to review the toxicology report from Michele's autopsy, prosecutors were told there was a toxic mix of drugs in her system. Her cause of death was changed to "undetermined."
In 2012, Martin was charged with murder and held on $1 million bail. In 2013, he was found guilty of murder and obstruction of justice. He was sentenced to 15 years in prison.
Willis was not charged in connection with the killing. Investigators found no evidence she knew, or participated in, the murder.
In 2017, Martin took his own life in Utah State Prison.
Michele's children are dedicated to eradicating their father from the legacy of their mother.
They've had "wife of Martin" removed from her tombstone. Alexis had her name changed to her mother's maiden name — Somers.
She now practices family medicine.
"I wanted to graduate having my mom's maiden name," she said. "I don't want to be Dr. MacNeill. I don't want to have any part of my dad."
"20/20" airs Friday at 9 p.m. on ABC.