Fullmetal boys | Edward X Reader

(Y/N) (L/N) is a child from a rich family, he is 13/16 years old (now) and had a older sister who would have been 18, but his parents and sister are no longer with him. What happens when the two childhood friends Edward and Alphonse meet (Y/N) after all these years, (Y/N) had no idea about what happened to Edward and Alphonse