Information: Dreamstar

Princess Luna's daughter, Princess Dreamstar has been living with her aunt, Princess Celestia ever since her mother turned into Nightmare Moon. It has almost been 1,000 years, and with the Summer Sun Celebration coming up, everyone is getting ready for the festivities except for Princess Dreamstar and Princess Celestia. They are preparing for Nightmare Moon's return and Twilight Sparkle's first-ever mission outside of Canterlot. Both are hoping that Princess Luna will return after the end of the celebration.
*I do not own My Little Pony*