Andy's no doubt answered it, but I've often wondered about a story one of my teachers told of someone he knew sitting next to Princess Margaret at a dinner.
King George V1 had been unwell, and the dinner guest thought he was being polite by asking 'I do hope your father's health is improved'. Despite their former cordiality, Princess Margaret apparently bristled and asked 'Are you referring to the King?'.
I often wondered whether there was a bit of a misunderstanding there about 'How's your father?'!