Task: Question Answering
Input (English): Passage: Ben Jones and Marion 'Howdy' Lewis are two easygoing, modern-day cowboys who make a meager living breaking wild horses. Their frequent employer is Jim Ed Love, a shrewd businessman who always gets the better of them. After they bring him a string of tamed horses and spend the winter rounding up stray cows, he talks them into taking a nondescript roan horse in lieu of some of their wages.
Ben finds (to his great and frequent discomfort) that the horse is unrideable. Rather than turning it into soap or dog food, he comes up with the bright idea of taking it to a rodeo and betting other cowhands they cannot ride it, thereby doubling their earnings. Along the way, the duo stop to help two none-too-bright strippers, Mary and Sister, with their car, which has broken down. Not knowing much about cars, they give them a ride to the nearest garage, but end up getting to know them better (going skinny dipping with them) and taking them along to the rodeo.
Everything goes as planned; nobody is able to stay on the horse. Then the animal suddenly collapses and Ben spends all the money they've won for veterinary help—and a new stable to replace the one destroyed by the roan when he recovers. In the end, Ben and Howdy end up right back where they started, with only the roan to show for their efforts. 
Question: What are the names of the persons that the cowboys take to the rodeo?
Output (English): Sister.