

Also, Arthur is one of the few "traditionally" heroic Nohrians, while Effie specifically mentions a few times that she and Elise came to be good friends during Elise's trips to the underground. Elise, on the other hand, recruits Effie and Arthur from the capital’s underground streets, and both start as commoners beforehand. Another contrast Elise has in comparison to her older siblings are their retainers of choice: Xander, Camilla, and Leo each have one retainer with shady backgrounds and personalities (Peri, Beruka, Niles) and another with mysterious origins (Laslow, Selena, Odin).Thus, it makes it all the more tragic that her death in Birthright triggers Xander's Despair Event Horizon and eventual Suicide By Hoshidan Army. Despite Leo's supposed annoyance with her at the beginning of the game, the Nohrian siblings probably encouraged her Genki Girl personality as well as her class choice. Further Fridge Brilliance on Elise: it's actually commented on a few times throughout the game (mainly by Camilla and Corrin) that she's a light amid all the other darkness that the Nohrian siblings had to deal with.probably to keep her safe and to make her a sort-of symbol of the innocence they could never truly have. Which explains why she's a healer instead of a combatant: Xander, Camilla, and Leo wanted her to not have to spill blood, and instead give her the chance to heal wounds. And even more: since the in-fighting died out after Elise's birth, the other surviving royal children probably did their best to keep her outside of battle as much as they could. It makes sense to have the eldest son and legitimate heir, as well as at least two of said half-siblings, be extremely skilled in combat as a way to survive this sort-of "civil war" among the nobles the Hoshidan siblings had their own problems, yes, but they still had somewhat of an advantage in such regards. Additionally, the Nohrian Royal Family was stuck in the middle of a horribly bloody Decadent Court where Garon's concubines were total bastards to each other and each other's kids, with more than one casualty among the children and probably among the concubines.The one Nohr sibling who isn't promoted is not only the youngest sibling, but is also a healer, which are among the most difficult units to level up in Fire Emblem games.

It makes sense since Nohr is a militaristic and glory-seeking kingdom, it's more likely the Nohr siblings would have been in more battles and thus have the chance to go into stronger classes. Most of the siblings in Nohr are already in promoted classes while the Hoshido siblings aren't.Adding to the Birthright point, adopting non-related children (and even adults) into a family for influence or one without a capable heir had been a practice in Japan for centuries.

The Hoshido path is called " Birthright" and not "Bloodline", after all.

Her Heroic Sacrifice is what kick-starts the plot. Not only that, but Mikoto is still your birth mother, and she still raised the Hoshido siblings as though they were her own children.After all, Ryoma knew all along that you weren't related to him by blood, but he still fights to bring you back home. It's easy to argue that it invalidates the idea of choosing between your bloodline and the people who raised you, but it does reinforce the idea that the Hoshidan and Nohrian siblings are not so different. The reveal that you and your Hoshidan siblings are Not Blood Siblings.
