Sleepover outfit essentials Sleepover outfit, Sleepover essentials Bitty Backpack Eloise's Sleepover Soiree Eloise Accessories Eloise Sleepover Party Ideas. Our Bitty Backpack in Eloise's Sleepover Soiree is made for busy days and stylish mischief! Easy to wear and easy to pack, this backpack is perfect for books, toys, ballet shoes or other extremely necessary things. Whether heading out for the day or off to cause a little trouble, this backpack is ready for it all. We are so excited to join Eloise in celebrating 70 years of mischief and magic with a collection as timeless as she is. Inspired by vintage charm, playful spirit, and classic style. Based on the Eloise books written by Kay Thompson, illustrated by Hilary Knight and published by Simon & Schuster. 2025 Eloise Enterprises LLC. All rights reserved.