How can one deal with a father whose condition has deteriorated after his association with a woman suspected of practicing sorcery, and he refuses to go to a shaykh or undergo ruqyah, and the children do not wish to resort to sorcerers to undo the magic?

Magic has an effect on a person and can separate a man from his wife. The Prophet, peace and blessings be upon him, was afflicted by magic, and its effect varies according to its intensity. Practicing magic and visiting sorcerers is forbidden, for whoever goes to a soothsayer or a diviner and believes him has disbelieved in what was revealed to Muhammad. Staying away from sorcerers and supplicating for your father's recovery is the correct approach, for Allah is near and responsive to those who call upon Him.