A 7-year-old girl has died and her 3-year-old sister is missing after flash flooding sent torrents of water into a narrow canyon in the Utah desert. Authorities said Tuesday that at least 21 others escaped the flooding in Little Wildhorse Canyon. The Emery County Sheriff’s Office says crews found a piece of clothing believed to belong to the missing child miles away from where she vanished. Dozens of rescuers are combing the area with help from helicopters. The canyon is considered a family friendly hike with curving, colorful walls, but it can turn dangerous when desert rains flow over the hard earth and quickly fill the narrow canyons.