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Original Description:
 
SOooo these were some ideas i had to explain why i draw Pinkie with feathers as a pegasus!
 

 
She has a grandmother that was a pegasus!
 

 
1.-Here you can see my design for Igneous Rock parents! I don’t have names for them (even tho in the series Igneous Rock’s father was named! still, i wanted to change that!)
 
His father was a rockstar, or something like that! and his mother was a herbalist. Both loved each other very much, and since day one, they knew they were meant to be with each other.
 

 
2.-My headcanon designs for Surprise and Igneous, and yeah they both are very different from their parents (their cutiemarks are very different) still, their parents will support them no matter what. SOo Igneous has that color mane because of his dad, and so Pinkie has it because of Igneous! i kinda liked this idea, it could have been awesome to see a younger self of Igneous Rock with pink-ish mane. In that picture he didn’t had his cutiemark yet.
 
Suprise is a very loving older sister, after all, since little, she wanted to have a brother!
 
Her personality is similar to Pinkie! still, she’s unique in her own way. Pinkie kinda reminds Igneous of his older sister.
 

 
3.- Igneous Rock and Cloudy Quartz, how did they met! well, like his father, Igneous was interested in being a rockstar, but not as something to do all his life, he just did it for fun.
 
In a concert he met Cloudy, she just LOVED the way he did sing in stage, and Igneous was very flustered by this, it wasn’t the first time a mare told him cute things like that, but this time for him it was different.
 

 
4.- I wanted to draw all the kiddos with their different coats, some have feathers in them, and others no, i wanted color it like that so i don’t do spoiler of future headcanon designs.
 
YEAH i included Octavio Pie with the girls! actually i didn’t know Pinkie had a brother!
 
so i just loved the idea of drawing him aswell. He and Pinkie have a rivarly , still, they both love each other!
 

 
Extra: see my art for surprise’s cutiemark! i wanted to re-make the one she had in her first design!