Daniel, a recent college graduate, is on the his way home for Christmas from his new job. He gets caught in a snowstorm and is taken in by an elderly couple who provide him with food and shelter. After the snowplows have cleared in the road. Daniel proceeds home. Daniel's father, Fred, is most appreciative of the elderly couples actions and in a letter promises to pay them $500. The elderly couple, in need of funds, accept Fred's offer. Then, because of a dispute with Daniel, Fred refuses to pay the elderly couple the $500. Can the couple hold Fred liable in contract for services rendered to his son?