But Kelsi emerged soon after to join her cousins in the stream. "She got out of the tent because she couldn't find her shoe," Sevy, Kelsi's grandfather, said.
In that moment, the mountain lion struck. The adults in the family heard screaming - one of the 10-year-old cousins had witnessed the ambush. And as they ran toward the sounds, they saw the cat holding Kelsi in its mouth.
"The cat bit Kelsi on the side and tried to pick her up and drag her a little bit," Butt told East Idaho News. When the animal could no longer keep the child in its teeth, it attempted to grip her in its paws.
The Butts rallied to Kelsi's defense. They hollered at the animal until it gave up and fled as swiftly as it had come.
"The family began yelling at the cougar," said Gregg Losinski, a conservationist with the Idaho Fish and Game Department, to the Rexburg Standard Journal, "and it dropped the girl and fled."
Mountain lion attacks on humans are rare. In one study of reported attacks in the US between 1950 and 2009, researchers found 141 victims and 15 deaths, with reported attacks peaking in 1990.
When mountain lions prey upon children, about one in four attacks are fatal, a group of Canadian scientists concluded in a 1998 survey of 50 attacks. Should a big cat attack, anecdotal evidence suggests fending it off with a rock or stick can be successful - though experts warn that bending over to pick up a weapon, or to lift a child, can expose vulnerable necks.
In Kelsi's case, the sound was enough fury. The animal disappeared after letting the child go relatively unharmed, considering the circumstances. "She is doing fine," Sevy told East Idaho News. "Her great-grandpa gave her a priesthood blessing and told her she will have stories to tell."
The girl was treated for scratch marks and puncture wounds on her arm, thigh and back, and was given a shot for rabies. Quick thinking and vigilance, the Fish and Game Department said in a press release, averted a tragedy. Butt was not immediately able to respond to a message from The Washington Post for comment.
As for the mountain lion, a young female cat was found nearby the camp early Saturday. Authorities recruited Mike Pimentel, a local hunter, to track the cat; his hounds treed a mountain lion around 2am, according to the Fish and Game department. The lion was killed by Madison County Sheriff's Office deputies.
Through it all, Butt said she knew Kelsi was going to make it through the attack, as she told East Idaho News. "I just had this comfort that she was okay and I felt like angels were there protecting her," Butt said. And to show a mountain lion attack can't keep a preschooler down, Kelsi was firm in that she wanted go to church on Sunday to display her injuries to her friends.