Este sitio web fue traducido automáticamente. Para obtener más información, por favor haz clic aquí.

FIRST ON FOX - A deceased Utah man allegedly killed by his wife, a children's book author, last year "had reason to believe" she was having an extramarital affair during marriage, according to his family's spokesperson.

Prosecutors say Kouri Richins, 33, poisoned her husband, 39-year-old Eric Richins, with fentanyl on the evening of March 3, 2022, at their home in Kamas, just outside of Park City, while their three young sons were sleeping.

"He'd had concerns previously, and he also had reason to believe she was having a relationship and that was continuing through their marriage … apparently in person," attorney Greg Skordas told Fox News Digital.

The couple also had financial disagreements prior to Eric's alleged murder that Skordas could not expand upon.

UTAH CHILDREN'S BOOK AUTHOR, HUSBAND SPARRED OVER ‘CURSED’ MANSION BEFORE HIS ALLEGED MURDER

Kouri and Eric Richins smile together

Utah prosecutors are accusing Kouri Richins, 33, of poisoning her husband Eric Richins, 39, with fentanyl last year at their home in Kamas outside of Park City while their three young sons were sleeping. (Facebook/ Kouri Richins)

Court documents obtained by Fox News Digital suggest the couple had been arguing about the purchase of a multi-million dollar property just before Eric's March 2022 death.

Warrants show that Kouri closed a deal on the 22,000-square-foot home a day after Eric's death on March 5 despite the fact that Eric had plans to tell her not to purchase the mansion. She then tried to sell the home, which is currently under contract for $3.75.

UTAH CHILDREN'S BOOK AUTHOR CHARGED WITH FATALLY POISONING HUSBAND

Eric suggested to those who knew him that he feared for his life prior to the alleged poisoning and had taken his wife off of his will. The month prior to his death, on Valentine's Day in 2022, Eric Richins suspected his wife was trying to poison him, a warrant for her arrest states.

Eric and Kouri Richins at a football game

Charges filed against Kouri Richins are based on officers' interactions with Richins and an unnamed acquaintance who apparently told authorities that she had sold fentanyl to the mother of three.  (Facebook/ Kouri Richins)

"Eric and the Defendant had a Valentine's Day dinner at their Kamas home. Shortly after the dinner, Eric became very ill," a warrant for Kouri's arrest states.

"Eric believed that he had been poisoned. Eric told a friend that he thought his wife was trying to poison him," the warrant reads. Kouri also apparently tried to poison him on a trip to Greece a few years ago, another warrant states.

UTAH MAN FEARED FOR HIS LIFE PRIOR TO ALLEGED POISONING BY CHILDREN'S BOOK AUTHOR: WARRANT

"He had told some members of the family that he thought she was trying to hurt him, and said at one point, ‘If something happens to me, check out Kouri. I think she’s trying to kill me,'" Skordas said.

Kouri Richins, Eric Richins and their three sons

Eric Richins had five times the lethal dosage of fentanyl — an opioid that is 50 to 100 times more potent than morphine — in his blood. (Facebook/ Kouri RIchins)

On March 3, 2022, the night prosecutors allege that Kouri Richins killed her husband, she allegedly served her husband a cocktail to celebrate a home sale. Kouri owns a real estate firm called K Richins Realty LLC.

LORI VALLOW TRIAL: HEAR ‘CULT MOM’ AND HER SISTER SPEAK AFTER VALLOW'S CHILDREN FOUND DEAD

She later told authorities that she had left him briefly to check on one of her three sleeping children and that when she returned, she found him unresponsive, according to the warrant. 

Kouri and Eric Richins smile together

An obituary for Eric Richins describes him as an "avid outdoorsman and dedicated hunter." He enjoyed helping his family's cattle ranch and growing his "successful" masonry business. The obituary also describes him as a committed family man. (Facebook/ Kouri Richins)

Eric Richins had five times the lethal dosage of illict fentanyl – an opioid that is 50 to 100 times more potent than morphine – in his blood, according to the medical examiner. Kouri Richins is also facing charges of possession of GHB, commonly known as the "date rape drug."

UTAH STUDENT AT ‘WORLD CLASS’ BOARDING SCHOOL DIED OF SEPSIS AFTER COMPLAINTS WERE IGNORED: LAWYER

Eric's family wants the public to know that he was a "good man" who "didn't take drugs" or have any kind of drug problem. An obituary for Eric Richins describes him as an "avid outdoorsman and dedicated hunter." He enjoyed helping at his family's cattle ranch and growing his "successful" masonry business. The obituary also describes him as a committed family man.

Kouri Richins' sold mansion

Warrants show that Kouri closed a deal on the 22,000-square-foot home a day after Eric's death on March 5 despite the fact that Eric had plans to tell her not to purchase the mansion. (TownLift, Will Scadden)

"Eric did absolutely everything in his power to provide his family with every possible opportunity to learn, grow, and have fun," his family wrote.

UTAH HIKER, 70, FIGHTS OFF MOUNTAIN LION WITH A ROCK AFTER HE'S

An unnamed acquaintance apparently told Summit County authorities that she sold fentanyl to the mother of three, who had asked for "some of the Michael Jackson stuff," the warrant states.

Kouri Richins headshot

This photo provided by KPCW.org shows Kouri Richins at the KPCW studio in Park City, Utah, April 12, 2023.  (KPCW.org via AP)

"I think they feel . . . a little bit relieved," Skordas said of Eric Richin's family and their response to Kouri's arrest. "They've been working with the county attorney's office and local law enforcement. . . . I think they're trusting the system is going to work, and they feel comfortable that the county attorney wouldn't have brought a case if she didn't feel she had a strong case."

Kouri continues to argue in a 2022 lawsuit with her sister-in-law that she is entitled to her late husband's $3.6 million estate due to a prenuptial agreement.

The mother of three sued Richins-Benson for $3.6 million, alleging that she is still a trustee due to her prenuptial agreement. Richins-Benson, in turn, argues that Kouri is not entitled to her brother's estate, according to civil court documents obtained by Fox News Digital.

Eric Richins holding a deer with his son

Eric Richins took Kouri Richins off his will prior to his death; his estate is worth about $3.6 million.  (Facebook/ Eric Richins)

The day after Eric's death, his sisters apparently went to the couple's Kamas home and "began threatening and verbally accosting Kouri," a 2022 complaint states.

CLICK TO GET THE FOX NEWS APP

Richins' arrest comes two months after she appeared on TV to promote her children's book about grief, "Are You With Me?"

A description for the book, which sells for $14.99 on Amazon, states that "Are You With Me?" is "a must-read for any child who has experienced the pain of loss, and for parents who want to provide their children with the emotional support they need to heal and grow."