Alicorns and pegasi

Ok before this story starts I have to explain a bit. Gleaming Spectrum is a gray pegasus stallion with a dark blue and orange mane.  Platinum Note is his biological daughter. She is about 12.  She is hot pink with a hot pink and orange mane. Her stepsister is a white teenage pegasus with a baby blue and pink mane. Shimmering Beat is her name she was an orphan but got adopted by a unicorn who abused her. The same one that Gleaming married and divorced. However when they were in court the unicorn attacked Luna for saying Gleaming had all the rights. Gleaming blocked they spell by jumping in front of Luna and Celestia gave him the job as one of Luna's guards. I would have put this in the story but I'm not sure how.  

Platinum bounced happily along side her sister. Her dad was in town.Not only that but he was with the princesses. She never met them before and today was the day. After the announcement her dad was going take them to meet the Princesses. Shimmering was happy too she finally was done with that wicked unicorn mare. "Just be careful sis" Shimmering said " You wouldn't want a bruise before meeting the princesses" Platinum looked at her sister and said" Who knows I might get me cutie mark for it" Shimmering smirked as she said "Would you really want a cutie mark for falling? " " No but I'm tired of waiting you have yours" Platinum reply pointing to Shimmering's cutie mark which was a drum surrounded by lines that represented shimmering.(Note Shimmering Beat). Before she could say something Platinum ran off and tacked an armored stallion.  "Daddy!!!" Platinum basically shouted "Hey sweetie pie! Enjoying yourself? " Gleaming said "Other than obsessing over her cutie mark yes she is" Shimmering said hugging her dad. "Okay girls this will be over quick so hurry and sit in your seats. Or I might have to leave before you get to meet the Princesses" Gleaming said nuzzling his daughters.  "Bye dad!!" The girls said in unison.