I’m not sure if it really will involve Mirakel, but I would say the dad is aware of his part in this, and even if you assume someone is manipulating him, if you go by the short flashback shown he was always planning to do this. Even before Mirakel and Lucia were born.
So yeah he’s very shitty does not deserve forgiveness.
As for Mirakel I personally don’t think we know enough yet. She comes of as your typical villainous sister but she also doesn’t.

So on the latest chap the father has this theory that someone might controlling his thoughts or whatnot about the FL.
Well I did think so. I believe Miracle is kinda sus yk? Like a typical villain daughter who’s acting like an angel but she’s controlling everyone with dark magic or sum. Butttttt pls no matter what happens don’t forgive that father he’s shtty and he admitted it himself the only sane one here is the knight and his bro who realized her upbringing (▰˘◡˘▰)