Obviously it is horrible to fire someone in these circumstances. I wonder what I would do though? Lets say you have an employee that is completely and totally

Obviously it is horrible to fire someone in these circumstances. I wonder what I would do though? Lets say you have an employee that is completely and totally incompetent, but their child has cancer and will slowly die over the next two years. Do you just be compassionate and try to minimize the harm having this person around causes? What if you can't afford to keep an extra person around? I don't think this as easy of a situation as I would like it to be.