Is a 21-year-old girl's refusal to live with her stepmother after her mother's death considered an act of disobedience to parents?

It is obligatory for children to please their parents, and it is forbidden to harm them. The Lord's pleasure is in the parents' pleasure, and His displeasure is in their displeasure. A father has guardianship over his daughter even if she grows up; she cannot marry or leave without his permission. This justifies the daughter remaining in her father's custody after the age of seven, and even after puberty. The father has the right to prevent his adult daughter from living alone. As for the father remarrying after the mother's death, it is a legitimate right, and the children's refusal of it is selfishness. Children must obey their parents in matters that benefit them, even if it entails hardship for the children.