Is a daughter considered undutiful to her father if she does not study medicine—despite her desire to study Sharia—and her father falls ill because of her refusal?

The father's right is great, and honoring and obeying him is obligatory in what is rightful. However, it is not considered rightful for a father to compel his child to study a field the child has no desire to pursue, and the child is not disobedient by disagreeing with his father regarding the field of study.

Therefore, the daughter is not obliged to obey her father in studying medicine, and she will not be considered disobedient by not doing so. However, if studying medicine does not harm her, it is better for her to obey her father, especially if she knows that her father will become ill if she disobeys him. In this case, it appears that she is obliged to obey him.

And if her father forbids her from observing a voluntary fast, she must obey him, unless his prohibition is for an unsound reason; in that case, she is not obliged to obey him.