What is the ruling on doing something that is doubtful if it will anger or sadden one's parents?

If the parents command something or forbid it, and they have a benefit in it without harm to the child, then obedience to them is obligatory. However, if the daughter is not certain that her action will anger them, and they have not forbidden it beforehand, and the action is permissible, then it is not unlawful for her to do it merely based on doubt about their anger. In the event of their anger, an apology can be offered that it was not known that this would anger them and that they had not previously forbidden it.