Based on nothing, only my guess... maybe she said sth to blame the mom for tthe death of the little brother! of course, unintetionally...
This is also my guess
I think, in the battle of custody, she says something that kinda hinting SuJeong is not a good mom. That’s why she lives with her father and the gossipy-news right now kinda digging up this problem.
I also think one of the reason she decided to “attacking” SuJeong is related to the death of the little bro. Like even she wants to live with SuJeong, she will be definitely hated because she is the reason the little bro died.The perpetrator might be the father or the horrible aunty.
what did the daughter do? i want spoiler please tell me... what did she do to her mom????