Daughter of the moon.

Today was a special day.The day when Twilight Sparkle was coronated a princess.Equestria was put to a fourth princess balance.luna was sad inside.she had thought that her daughter would be the fourth princess.At the night Luna finnaly decided to tell Celestia the truth.''Celestia,i have something to tell you.''she said with sadness in her face.''What is it?''Celestia said worriying.Luna gathered all her bravery and said:''I have a child.''''What?for how long,who is she or he?''Celestia shouted.''Her name is Derpy Hooves.She is the pony whos birthday parties i always attend.''Luna said with tears in her eyes:''I i didn't know what to do,so i took her to the closest orphanage.''Luna kept talking.Then she started crying"I hoped that nopony would ever know.Please promise me you won't tell anypony.''Luna cryed hysterically''Of course i will not,but you must tell her.''celestia said with a faint smile on her face as Luna hugged her.luna calmed down and said:''I don't want to.I want to be her secret mom.''Celestia agreed:''Alright if you don't want to then okay but nopony must know.''

[spoiler][/spoiler]Derpy is invited to the gala.what will come off of it?