@Shizumu They're not...Ahjumma didn't adoptt haebom, she's just taking care of him. If it's about the past that "Taesung be brothers with Haebom" That is just a playful joke so the two can bond.
Replied to
No... This is so wrong you guys are brothers......
my theory : So this white haired guy is possible if he's in a coma and been dreaming and entering someone's dream (+lucid dream) but has a trauma that he cant even explain and avoid the question mc's been askin