What is the ruling on a mother caring for her sick maternal uncle, whose illness has caused her psychological and physical exhaustion, and would she be considered negligent if she is unable to keep up with the pace of his soiling of the house?

The basic principle regarding a sister's direct handling of her brother's private needs is that it is impermissible, except in cases of necessity, in which case men should undertake this task. If no men are available, then it becomes permissible for her, but only to the extent of the necessity. She should not look at his 'awrah (private parts) and should use a barrier. Patience and seeking reward from Allah are encouraged. It is permissible to place him in a care facility for the disabled if such facilities exist. If his sister becomes ill, there is no sin upon her for her shortcoming (in care), but if she recovers, her care for him becomes obligatory, as it falls under maintaining kinship ties and showing gratitude for the blessing of good health. If he is able to remove impurities from himself, it is not permissible for his sister to directly handle that; instead, she should assist him in cleaning the place, removing the impurity, and washing clothes.