Ariel Salaices is fighting for her life in a children's hospital in Knoxville, Tenn. (Stephanie Brown/Facebook)

Two swings undulated in the gentle afternoon breeze as 2-year-old Ariel Salaices prepared to zip down the slide in her family’s backyard in northeastern Tennessee.

Bikes were strewn around the wooden swing set, with forest-green seats that matched the trees surrounding the modest home in Mountain City, Tenn., near the borders of Virginia and North Carolina.

The peaceful childhood scene — which found Ariel playing with her older brother on March 15 — was punctured when a stray bullet came whizzing into the backyard, her family said. It ricocheted off a metal post and became lodged in the back of the 2-year-old’s head.

She fell from the slide and went running to her father, collapsing outside the house. Her father collected her from the ground and rushed her to a nearby emergency services unit, as Ariel’s aunt recounted on Facebook and on a GoFundMe page soliciting donations for the family.

From there, she was flown roughly 50 miles to the Johnson City Medical Center and then transferred to the East Tennessee Children’s Hospital in Knoxville.

Doctors kept her sedated through Saturday, monitoring her swelling and vitals as she continued to respond to touch. They determined that she had suffered a stroke, the family said.

On Sunday morning, a CT scan showed that the bullet had blocked blood flow to part of her brain, requiring surgery to place a drain on the side of her brain where she still had function. A piece of her skull was also removed to ease pressure on the right side of her brain, her aunt, Stephanie Brown, wrote on the fundraising page.

Although Ariel was stable over the weekend, her condition had worsened by midweek, according to local media. Neurologists were continuing to monitor the pressure inside her skull, her aunt said. The bullet had moved from the back of the brain to the front, she reported, but doctors were “happy where she stands,” given the circumstances.

Meanwhile, investigators in Johnson County, Tenn., were working to ascertain who had fired the errant bullet.

“The person who did this couldn’t have lived that far,” Sheriff Edward Tester told WYCB-TV. “Whether they know they did it or not. I think with all this information out there, I think they know who they are.”

He said the incident offered a lesson about firearm safety.

“If you’re using a firearm and doing target practice or hunting, make sure you’re looking beyond where you’re shooting,” Tester said. “Because that bullet may not stop where you want it to.”

Ariel’s parents were keeping watch at her bedside, Brown said. The GoFundMe page had raised about $18,000 for their expenses by Friday morning. The appeal included a photograph of the child breathing through a tube, a neck brace supporting her head.

Christina Salaices described her daughter as “spunky” — as “the sweetest little girl in the whole wide world.”

“She’s got a little attitude,” Salaices told WJHL-TV. “We’re hoping to get that back.”

Stray bullets have imperiled the lives of scores of American children. According to the Trace, a website focused on firearms, at least 150 children younger than 13 were struck by stray bullets in the first half of 2017.

A 5-year-old in the Bronx. A 4-year-old in New Orleans. A 2-year-old in Memphis. The circumstances differ, but in most cases, an innocent child was caught up in someone else’s feud. The youngest accidental target was 3 days old.

In a case last year, the victim was herself a gun violence advocate worried about what she saw around her in Milwaukee. Sandra Parks, 13, had written in an essay, published posthumously by Milwaukee magazine, observing that “we are in a state of chaos. In the city in which I live, I hear and see examples of chaos almost everyday. Little children are victims of senseless gun violence.”

Parks died in November when a stray bullet was fired into her home.

Ariel’s relatives were struggling to make sense of how such misfortune had been visited upon their family.

Michael Sawyer, her grandfather, said he was oscillating between anger and sadness, “but I know that’s not going to change the outcome,” he told WYCB. “It’s hard.”

Speaking on local television from the hospital, the girl’s mother appealed for the person who pulled the trigger to come forward, saying it would help family members — who were gathered at Ariel’s side — find some peace of mind.

“God only knows how this even happened,” Salaices said.

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