Police: Woman charged with suffocating 3-year-old stepdaughter planned killing for days

"Happy Birthday baby girl!! Miss you dearly, fly high baby," Yadon wrote. "I love you so very much!!"

Vernal police officials said officers were called to the family's home Marcy 14 on a call of a child believed to be choking. Court records obtained by The Deseret News show that the first responding officer saw purple and black bruising around Arianna's left ear.

The officer determined the toddler “had been down for a period of time” and wrote that it was “immediately apparent that these injuries were not consistent with the details initially provided for the medical response.”

The News reported that Arianna was pronounced dead a short time later at a hospital. An autopsy conducted the following day showed she died of asphyxia due to suffocation.

Yadon and the girl’s baby brother were the only other people in the home when Arianna was killed, the court records show.

The Tribune reported that Yadon was taken into custody May 23, at which time investigators said she admitted while sitting in a patrol car that she caused Arianna's death. In a statement she gave at the police station, she said she used a blanket from Arianna's bed to smother the girl.

She used a child-sized CPR mannequin to demonstrate how she killed the girl, the Tribune reported. Investigators wrote that Yadon showed how Arianna struggled for four to five minutes while she held her down.

Yadon told detectives she waited 10 to 15 minutes after the girl was dead to call a friend, who called 911, the newspaper said.

"(She said) she had been planning and thinking about doing this act for two or three days" prior to Arianna's death, the court documents say.

It was unclear why Yadon wanted the girl dead. Her description of herself on one of multiple Facebook pages belonging to her is that of a "strong woman that loves her little family, is caring, is kind and ain't someone to mess with."

Arianna's obituary describes the little girl as having "the most beautiful smile and bright red hair." She was always smiling and giggling and 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'" little girl, the obituary said.

Arianna's grandmother, Christina Cook, told the News her granddaughter was cherished by those who knew her.

"She's our little angel. She was just our little red-headed angel. There's no other words to describe her, really," Cook told the News.

Cook said Arianna, when cautioned against approaching strangers, would say, “But Grandma, they were so sad. They needed a hug.”

Arianna would also take care of those close to her, particularly her older sister, who has autism.

"She did everything for her older sister. She made sure Naomi was taken care of," Cook said. "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. She was just that way."

Naomi knows Arianna is gone, but does not understand why, Cook told the newspaper. When they visit the toddler’s grave, however, Naomi knows her sister is there.

"She'll just lay there and kind of pat her grave and say, 'I miss you, sis. I miss you, sis,'" Cook told the News. "She does the same thing with her mama."

The girls' mother, Jessica Ortega, died in 2017, Cook said. According to her obituary, Ortega died at age 26 of complications from a stroke.

She was an organ donor and the family was able to meet the recipient of Ortega's heart, Cook told the newspaper.

“(Arianna) was so happy when she got to listen to her mama’s heartbeat in somebody else’s chest,” Cook said. “She was, like, ‘That’s my mommy.’”

Cook said she is plagued by thoughts of what her granddaughter went through when she was killed.

“She was adorable. Just to think that her stepmom did this to her, it's just, it's heart-wrenching,” Cook said.