Applebloom lost her mother at a very young age due to a sky carriage wreckage hitting the farm. she was incredibly upset over it, but she hides her anxiety and emotions about it via a cool, laid back facade. during her late teens, she finally ends up having a breakdown over it, and her friends Sweetie Belle and Scootaloo help her through it and help her talk about it and let all those negative emotions go.
 
when she grows up, she moves away from Sweet Apple Acres, roaming from city to city, taking on various jobs, whether they’re apple themed or not. Applejack objected loudly to this, thinking that family needs to stick together, but Applebloom stated firmly that “all birds need to leave the nest at some point, AJ.” and then she gathers her things and disappears, not being spotted again until 4 years later by Twilight Sparkle. Applejack realizes that even though her place was there on the farm, helping Granny and Big McIntosh, Applebloom’s place wasn’t. she needed to be free and choose her own path. Applebloom and AJ send each other letters and trinkets from Ponyville and whatever town Applebloom is in at the time, each slowly growing their collection of Sister Gifts.