Regarding whatever little A might have discovered in that box, and I'm BETTING on this hard but weirdly I have a feeling that uncle / mr A is NOT just an uncle. Since little A didn't exactly understood what it was in the box it was probably bc he couldn't read it. Idk how else to explain his confusion for now. And weirdly enough their bond is weirdly too close for it to be any uncle like relationship. But I might be hard wrong on that so it's a speculation with big BIG question mark.