Shall I go and see my advisor's father who is on his death bed? In my country in East Asia, it is extremely impolite if I don't do it when I have this information.
However, the US and the EU are known to be more &quot;professional&quot;, in my humble opinion. So, in the US, is asking the advisor about his father generally considered &quot;impolite&quot; or &quot;unprofessional&quot; from a professional point of view?
Unless you have some direct relationship with his father, this is not something we'd normally do in US, UK, or Australian culture. (I'm not sure if it's the same everywhere in the EU.)

A polite option might be to tell your advisor something like "I'm very sorry to hear about your father, please let me know if there is anything I can do."

If your advisor is from a different culture, that might change things.