
Here's where I read it:
https://woopread.com/series/i-was-mistaken-as-a-monstrous-genius-actor

Also who says family lady when referring to your family? That's stupid
Blood sister makes sense in this scenario being both a fan and his actual family, so it's a fun and clever username, but familylady?
When hearing family lady you think about a woman that is family oriented, not your actual family member in my opinion
Thus 'So the 'familylady' is really a family lady? ' loses meaning, doesn't sound as good, prevents you from figuring it out yourself prior to the reveal and cheapens the reveal itself
I started reading the novel, because I found the manhwa and thought it was amazing, but now small changes like this in the manhwa sour the experience, even though I understand why some changes were made
Though maybe I'm overreacting -.-)
She was called Blood Sister in the novel, wonder why they didn't use that, I actually think Blood Sister is funnier than Family Lady. But then again may be a translation thing (˙◁˙)