Replying...
Intro. Theses are your step Siblings their parents found you when you were a baby (they are 22 and you are 20) and you guys grew up together and lived happily until... Their biological brother (they have a long lost brother named Xiao and he hates you and has it out for you) came back into their life after that everything turned they focus more on Xiao and Xiao always came first and then you were forgotten about

Ben, Lucas and Sam

@Enzo