So, this is my take on Trixie’s family. Her parents were part of the elite group of Canterlot. Her mother was raised to be a perfect elite unicorn, which meant doing everything to keep up a perfect image. Her father was the captain of the royal guard, so he was rarely at home. When he was, the atmosphere was uneasy since him and Trixie pretty much had no type of connection. For her he was a complete stranger. Even with that, her father wasn’t a bad one. He always secretly came to her school plays, sometimes went to the park with her and would always hang her drawings that she would do on his office. He was pretty much there for her whenever she needed him, especially whenever her mother was busy going to parties. He just…he wasn’t the most emotional pony. After many years of harsh military training and having been through a lot of shit, it was very difficult to make him do any type of different expressions. He always had the same ‘I’m fucking pissed off’ expression no matter what.  
On the other hand, Trixie’s mother was always smiling and laughing. Attending various parties and balls. All to keep up her and her family’s reputation. Even though she appeared happy, she was pretty miserable on the inside. She secretly hated the elite life. It did not allow her to be free and her true self. Ever since she was a filly she was raised on what she should and shouldn’t do. An elite pony was intelligent and graceful, she absolutely needed to be that. Though when her cutie mark appeared, she was absolutely shocked. It was related to singing, to freely sing to her heart’s content. That was a big ‘no no’ for her father and mother. The most singing an elite pony would perhaps do was opera and, well, she didn’t like that. She felt like fate was playing with her. Being so cruel to give her a cutie mark, a propose that she would forever be unable to do. She hide her emotions and decided to keep on being the perfect pony. She ended up marrying Trixie’s father not because she loved him but because he would help her with her social status. And when Trixie’s cutie mark turned out to be related to magic performances, she taught her daughter the same. That a perfect elite pony wouldn’t do such silly things. That Trixie would find happiness doing something more ‘normal’. Trixie was sad and confused but since she believed her mother knew best, she foolishly trusted her.  
However, years later when Trixie was in her teens, her mother just had enough. Her anger and sadness couldn’t be kept at bay anymore. She just had enough. She was done with elite gatherings and the need to be the absolute best. One day she just left. She needed a fresh start and that meant abandoning her daughter. Trixie, of course, was completely destroyed. She was closest to her mother, rather than her father, and seeing what she did, Trixie just couldn’t wrap her mind around why her mother would do something like this. Her father didn’t exactly know how to react to his wife leaving them. So he pretty much just drowned himself in work. Her father tried his best to calm her but seeing as they weren’t close, Trixie turned into a very angry teenager. She felt abandoned. Like no one would ever love her enough. She grew to always be seeking love and acceptation of other ponies.
 
I’m thinking of naming Trixie’s mother “Lavender” and her father “Thunder”. What do you guys think? and did you liked the designs and background story?