Nopony has ever wondered what brought Pinkie Pie from the rock farm to Ponyville, not until the arrival of Diamond Tiara's cousin. Pinkie does everything in her power to avoid this pony. But when her friends notice that she hasn't thrown a party for the new arrival (as she usually does), something feels off. In truth, Pinkie Pie has a deeply repressed secret that she never once wanted to share with her friends.