I didn’t exactly read it except for the first few chapters out of curiosity. But from my understanding, Leila has no idea, Edwin did tho, he doesn’t really care.
The 2 saw L and E going dirty at night, E saw them but he doesn’t seem to care, and act normal in daytime. It seems to imply that Edwin play the role of a doting perfect father just for Leila. Leila was the only thing that actually matters for him. iirc someone mentioned in the beginning Edwin actually warned the 2 that they can do anything as long as they don’t break Leila’s heart in the novel (probably about keeping it hidden from Leila) (can’t remember if he actually said sth or it is just implied)

what you mean “his obsessed with his big brother”??? please, don't do that kind of genre bro