The force of impact cracked the helmet Delaney O'Connell was wearing
Credit: Facebook

A 10-year-old girl taking a ski lesson at a Michigan resort died Tuesday of a head injury after apparently losing control on the hill and crashing into a tree on New Year’s Day, authorities say.

Delaney O’Connell of La Grange, Illinois, was taken to the hospital after the accident at 2 p.m. on Sunday but died Tuesday of cranial cerebral trauma, or a closed head injury, the Kent County, Michigan Medical Examiner’s Office tells PEOPLE.

The force of the impact was so great “that it cracked her helmet and caused a serious brain injury,” her mother, Dawn O’Connell, wrote in a message posted on Facebook. “We are heartbroken.”

O’Connell added, “Life will never be the same for our family. We will miss our dear, sweet Delaney every single day.”

Delaney was in a class on an intermediate ski trail at the Crystal Mountain ski resort in Thompsonville and ahead of two other children and a certified ski instructor, resort spokesman Brian Lawson tells PEOPLE. Delaney, who had been attending ski classes at the resort since she was 3 years old, was classified as a Level 4 skier, “which means her skill and control far exceeded the terrain,” he said.

Though “she was a proficient skier,” he said, “she may have caught an edge or slipped a little bit. That’s when she struck a tree.”

It is unknown how fast she was going but “it’s clear there was loss of balance here,” Lawson said. The instructor “did exactly what she was supposed to do,” and summoned immediate medical attention, he said.

The girl was “unconscious, but alive” when paramedics arrived, Craig Johnson, Benzie County Medical Director, tells PEOPLE. She was transported to Munson Medical Center in Traverse City and then sent to DeVos Children’s Hospital in Grand Rapids, where she was pronounced dead, according to Lawson.

Delaney’s death was the fourth fatality in the resort’s 60-year history and the first child, Lawson said, which left the employees shaken. “It’s like they’ve lost a family member,” he said. “It’s been extremely difficult for them.”

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Fatalities at U.S. ski areas are rare. Of about 52.8 million skiers and snowboarders, 39 died last ski season, according to the National Ski Areas Association, a trade association.

Though “fiercely encouraged,” helmets are not required at Crystal Mountain or in Michigan, Lawson said. About 80 percent of people do wear them but New Jersey is the only state that requires helmets, calling for skiers or snowboarders under age 18 to wear the head protector, the NSAA says.

Evidence shows that helmets are “very effective” in reducing the rate of potentially serious head injuries, particularly at speeds up to about 13 mph, Dr. Jasper Shealy, an emeritus professor at the Rochester Institute of Technology who has studied ski-related injuries, tells PEOPLE.

At higher speeds, however — the average maximum speed was 27 mph in a study he conducted — the ability of helmets to prevent death drops, he says.

“If you hit a tree or another fixed object,” Shealy says, “you’re simply going to need more than a helmet to save your life.”

Still, he and other ski experts strongly recommend wearing one. “Wear a helmet by all means,” he says. “But don’t expect miracles.”