What is the appropriate limit for showing filial piety to a parent who makes unreasonable demands and refuses to take medicine except through trickery, and is it considered disobedience for the children to say to him, "We are tired"?

Filial piety is one of the most obligatory duties. Obedience to parents in what is good, serving them, and caring for them are incumbent, especially during their weakness and illness. Allah Almighty says: "And if either or both of them reach old age with you, say not to them [uff] and do not repel them but speak to them a noble word." If a parent commands something unbearable or harmful, obedience is not obligatory, and this is not considered disobedience. Filial piety is among the best righteous deeds and a cause for success in this world and the Hereafter.