I have a good handful of Musical OCs, including three half-Sirens.
 
Names/Ships:  
Elegy - Twilight Sparkle x Adagio Dazzle  
Love Song - Uh… she was originally just an OC to be adopted by a random couple, but I might make her a Pharynx kid? I’ll update the image if I go for that.  
Allegro - Pinkie Pie x Sonata Dusk  
Ballad - Sunset Shimmer x Adagio Dazzle  
Dance Party - Night Glider x Party Favor  
Electric Violin - Octavia x Vinyl Scratch
 
Edit: Yep. Officially made Love Song a Pharynx kid. Not sure who the other parent is though.
 
Base: fav.me/dbsskf8