Police: Arianna Stout Didn’t Make it to Her Fourth Birthday Thanks to her Step-Monster

Arianna Rose Stout
(Ashley Valley Funeral Home)

Two months before her fourth birthday, precious angel baby Arianna Rose Stout was smothered to death by her father’s wife, 24-year-old Mckenley Yadon, who admitted to police that “she had been planning and thinking about doing this act for two or three days prior to March 14 [2019],” according to court documents.

The depraved monster even demonstrated to investigators, using a child-sized CPR mannequin, exactly how she smothered Arianna with a blanket.

Before I get too deep into a rage-inspired rant, let’s go back and start at the beginning of this terrible, twisted tale.

Arianna Stout family
Newborn Arianna with her family in the hospital.

Arianna was born on May 19, 2015 to parents Jessica Ortega-Scheurn and Aaron Stout of Vernal, Utah, making Jessica’s autistic daughter, N.S., a big sister.

Two years later, on June 27, 2017, Jessica passed away at the age of 26 due to complications from a stroke, according to her memorial page. The family followed Jessica’s wishes to donate her organs and later was able to meet the recipient of her heart.

Jessica’s mother, Christina Cook, told KSL, “[Arianna] was so happy when she got to listen to her momma’s heartbeat in somebody else’s chest. And she was like, ‘That’s my mommy.'”

Jessica Ortega-Scheurn
(Hullinger Mortuary)

It’s hard to imagine something more heartbreaking than a 2-year-old and her autistic 5-year-old half-sister losing their mother at such tender ages, isn’t it? Well, my friends, it gets worse.

Jessica’s gravesite at Roosevelt Memorial Park in Utah

On March 14, 2019, police were summoned to 1536 W. 300 South in Vernal by a caller reporting a choking child who had become unresponsive. This is the home shared by Aaron Stout and his partner Mckenley Yadon (also known as Mckenley Stout; the couple was, according to Facebook, married on December 21, 2018). Also living in the home was the couple’s 12-month-old son, B.Y.S., and Aaron’s three-year-old daughter, Arianna.

Arianna Stout family
McKenley holding Arianna’s baby brother, and Aaron holding Arianna.

According to the officer who responded to the call, Arianna “had been down for a period of time,” according to the probable cause affidavit. The child was “unresponsive, not breathing, and cold to the touch,” and the officer noticed “dark purple and black bruising in front, on top, inside and around her left ear.” The affidavit continues, “It was immediately apparent that these injuries were not consistent with the details initially provided for the medical response.”

Arianna was rushed to Ashley Regional Medical Center, but about an hour later, despite the doctors’ best efforts, Arianna Rose Stout was pronounced dead just two months before her fourth birthday.

Sweet Arianna

An autopsy was performed, although the results were not published until May 23. In the report, the medical examiner confirmed Arianna died of asphyxia due to smothering. The manner of death was deemed murder.

Just so we’re clear, Mckenley and little B.Y.S. were the only other people in the home at the time of the incident that caused Arianna’s death, and, at not quite a year old, the likelihood that the baby caused his sister’s fatal injuries is virtually nil.

The same day the autopsy results were released, police interviewed Mckenley, who readily “admitted to smothering [Arianna] using a blanket on [Arianna’s] bed,” according to the police report. As I mentioned in the first paragraph of this post, Mckenley told police she had been planning Arianna’s murder for at least two days prior to carrying it out. Acting out the murder for police on a CPR dummy, Mckenley explained how she smothered Arianna with a blanket from the girl’s own bed, describing in detail her “body movements and struggle during this event as she maintained consistent force over [Arianna’s] airway.” She told police she “maintained the force” for four to five minutes, only stopping when Arianna stopped struggling.

Mckenley Jordan Yadon-Stout’s booking photo.
(Uintah County Sheriff’s Office)

Police wrote, “Mckenley advised she waited 10 to 15 minutes after [the child’s] death to contact a friend who she provided an inaccurate account of events, thus resulting in the initial 911 call.”

Mckenley was arrested following her enlightening interview/confession. She has since been charged with aggravated murder, a first-degree felony, and child abuse, a second-degree felony. She is being held in Uintah County Jail without bail and is scheduled for her next hearing on June 3.

Arianna Stout
Arianna with her baby brother.

Now, enough about the sea hag who confessed to ending this precious child’s life. Let’s talk about Arianna, who deserves to be remembered for the sweet soul she was.

Arianna’s maternal grandmother, Christina Cook, recounted to Fox13 how Arianna spent every other weekend with her. “She was just the most beautiful little redhead angel that was born. She was one of those little girls that went out of her way to make sure that the other person was happy.”

What a truly beautiful child.

From Arianna’s obituary, posted by the Ashley Valley Funeral Home:

“During her short time here on Earth, she touched many lives and was loved by all who met her… Arianna was born May 19, 2015, with the most beautiful smile and bright red hair, our beloved shining, always smiling and giggling, playful, light of our lives and the star of our hearts, happy girl, she loved her family and animals… Her dad and uncle Daniel made sure she played in the dirt and rode four wheelers, while at the same moment she was a put me in a dress let’s play tea party… Arianna joins her mother Jessica Ortega…”

How desperately, horribly sad.

In an interview with KSL, Christina said that Arianna had no sense of “stranger danger” and would give hugs to anyone, from elderly women at church to fellow shoppers in the store. When told not to approach strangers, Arianna would say, “But Grandma, they were so sad, they needed a hug,” Christina said in her May 24th interview.

Grandparents Troy and Christina Cook

Arianna’s family was, according to KSL, “dumbfounded” by the revelation that her own step-mother perpetrated her murder. “She was adorable,” Christina said. “Just to think that her stepmom did this to her, it’s just, it’s heart-wrenching. And I told them any time, any time you feel like you can’t handle [the kids] or whatever, just let me know and I’ll come get ’em. I’ll come get her, I’ll take her.”

According to Christina, not only was Arianna her grandparents’ “pride and joy,” she was also the “protector” of her autistic sister, N.S., who is now seven years old. Christina and her husband, Troy, were granted permanent custody of N.S. in January of this year.

Aaron and McKenley with Arianna and her two siblings. (Facebook)

“[Arianna] did everything for her older sister,” Christina told KSL. “She made sure [N.S] was taken care of. She made sure she washed her sister’s hair all the time in the tub, and she was just taking care of her big sister.”

Arianna’s gravesite at Maeser Fairview Cemetery in Vernal, Utah.

N.S. knows Arianna is gone, Christina said, but doesn’t understand why her sister can no longer play with her. “And then when I do take her to her sister’s grave, she knows, ‘That’s my sister,’ and then she’ll just lay there and kind of pat her grave, and say ‘I miss you, sis, I miss you, sis.’ She does the same thing with her mama.”

I cannot fathom the depth of this family’s loss and grief, first losing Jessica to a natural but tragically early death at age 26, and less than two years later, having little Arianna ripped out of their arms by the woman her father trusted to protect her.

“This is just something I wouldn’t wish on anybody, not even my worst enemy,” Christina told Fox13. “It’s just unbearable. It really is. It’s unbearable.”

Christina said she didn’t see any signs that her granddaughter was being abused, and that she hopes McKenley’s arrest will bring justice for Arianna. “I think there’s comfort there, knowing we’re going to get justice for her. We know Arianna is still with us.”

Arianna can now rest, safe in her mommy’s arms.

Good lord, this story made me sad. Below is a gallery of additional photos I couldn’t cram into the post but are absolutely worth seeing. Click to flip through and view a descriptive caption for each.

Click here for my ongoing coverage of Arianna’s case.

Sources: KSL, Fox13, Ashley Valley Funeral Home, Facebook


  1. This is my 10 year old son Aidens half sister that McKinley murdered Aaron stout is his dad it is so horrible and aaron is also going through so much as well and it also hit me pretty hard because of my son prayers and love to all who are devastated by this i wish tourtur was a sentence they can give to people who harm children or murder them

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