She is. Spoiler alert
Penelope will meet her soul which is trapped in the mirror and will see how her body was occupied by Leila the day she went missing. It's a tragic story.
Wait woah can you explain that better please ✧(>o<)ﾉ✧
I'm not sure it's been a while but if I remember correctly, the real Yvonne died and Leila, the sect leader occupies her body. She wasn't suppose to come that early because the only reason she comes to the family is because of Penelope. She wants to kill her.
Apparently, Penelope is the last witch by blood still alive or something like this, and only witches can pose a threat to the sect. By killing the last one, the sect are free to dominate the world.
Since Penelope came to them, Fake Yvonne saw her immediately as a witch, which is why she started to move earlier than planned.
I don't remember exactly how witches poses a threat to the sect but this might be why she is able to see the real Yvonne in a mirror. We need to read more to understand fully all the more about that.
Yes, just like what Risshi said. Later when Penelope gets trapped in the mirror -I think it was already in the extras - she sees Yvonne's life, how she struggled to get her body back, she was always near and saw the life of her family but couldn't defeat the monster in her body and eventually was defeated (this is a really sad part) and she finally moves on and asks Penelope to tell her family her farewell.
Ok that is actually so sad! Thank you for the spoilers : D
Are we really sure Yvonne is actually their daughter anyway? We know Penelope got picked up on the street and the duke remembers how he found her and the family would recognise their own daughter/sister, but couldn't some form of magic be involved there too. The timing they found her is too good and she also has pink hair anyway.
Well tbh we just hate Yvonne so why would u want her to be even biologically related and have any advantage so I'm hoping for the unlikely lol : /