What is the ruling on a man divorcing his wife because she was late in visiting her sick father in the hospital?

It appears that a husband divorcing his wife because she visited her sick father is reprehensible (makruh), because it is not a valid reason for divorce. Rather, visiting one's parents is an act of kindness commanded by Islamic law. The husband should have, more appropriately, helped her in her dutifulness to her parents. This divorce falls under the category of reprehensible acts (makruh) that are without cause.