As the basically polar opposite to Discovery is his younger, hulking brother Ambrose; first recorded male alicorn in Equestrian history. His birth was seen as a major omen of some great shift happening in the nation, and little Ambrose had mountains-worth of expectations heaped onto him from day 1. Well, lo and behold, being expected to basically turn water into wine before the age of 5 did a number on the lad growing up, and the more ponies believed that he’d be all the elements rolled into one guy, the more he retreated into himself out of fear of not being able to live up to those expectations. Ambrose basically just stuck to his comfort zones, usually involving farming with pa and Auntie AJ (and sometimes Granny), being helpful around town, and assisting his brother with whatever thing he’s working on at the time. Can’t disappoint ponies if you don’t try…never mind that now ponies see him as a goof in a family full of ponies who all achieved something (his mother the princess, his brother the scholar/mechanical wiz, his aunt and uncle the king and queen of an empire, ect). His talent lies more in agriculture, and would rather sturdy farming, partly as an excuse to hide away for the rest of his life if possible.  
 
I wanted to make it so that, while these two are radically different, they’re still tight and support each other as best they can. Discovery isn’t the best at emotions but knows his brother looks up to him and does his best to include Ambrose in whatever his latest project is. Ambrose meanwhile, looks up to Discovery because (in his eyes) he’s everything Ambrose wishes he is; intelligent, well-spoken, composed, careful, everything a future prince is supposed to be. While a usually chipper and friendly guy, Ambrose hides a lot of insecurities and expresses that in the form of attempting to be generally helpful. He wishes he could be seen more for the pony he is outside of what his magic is “supposed” to do for others, but is so worried about letting others down he rarely knows where to start. Discovery hates how his brother feels like so many ponies defined him by his magic since he was a baby, and part of why he wants to make a more technologically advanced Equestria, is so that ponies put less stock in magic, freeing his brother from the burden of those expectations.  
 
There’s way more but I’m just going to leave it for now, since this is a lot for two sketches where the lines aren’t all correct.