Is a mother's prayer against her daughter, out of anger towards her, acceptable? And is the distress that afflicts the daughter in her life a punishment for her displeasing her parents, or a mercy from Allah?

Angering and bothering parents is an act of disobedience (ʿuquq), and it is one of the gravest major sins. The supplication of parents against their child is answered, but the mother should be wary of supplicating against her children. A harsh temperament and quick anger are not an excuse for mistreating them, and one must repent to Allah for the disobedience and hasten to treat them with kindness.