The Grand Galloping Gala was something Sweetie had been looking forward to all year, she finally got to wear the pretty dress her sister made for her! When she tried on the dress though she realized something, what if she had to use the little filly’s room while she was at the Gala? She couldn’t take off the dress by herself, and Rarity wouldn’t let her anyway.
 
Rarity came up with a solution for the evening out, and Sweetie as embarrassed as she was by the thick diaper taped around her rear, was loving every moment of it
 
Description by Thunderchaser22