Pinkie Pie is eager for her friends to meet her visiting older sister Maud Pie, whom she says has much in common with each of them. When Maud arrives, however, Pinkie's friends find her to be a deadpan pony with an unusual interest in rocks, and fail to find any common interest with her despite their best efforts. Upset by her friends' inability to befriend Maud, Pinkie decides to help them by constructing an obstacle course that combines all of their interests, including a giant pile of rocks for Maud. While demonstrating the course, Pinkie is nearly crushed by a boulder, but Maud rescues her. Pinkie's friends realize that Maud cares for Pinkie as much as they do, and offer their friendship to Maud over their shared bond before she leaves, which she gladly accepts, albeit without expression.