Responses
I can see the MC not realizing it when he barely talks to her and tries to avoid her if he can help it. He's also extremely busy with trying to establish himself to get married and survive.
We weren't talking about whether he knows or not tho, we were talking about the readers not knowing. I was curious why OP didn't know she was his sister in his past life when she practically said as much in previous chapters.

Ok so Mc and the girl who likes money so much cus she was also reincarnated gotta be siblings right-