Ways that are not fun to wake up:

Around 10am, after a restless night of about 6 hours, get a phone call. The phone call is from a stranger. This stranger knows your name.

She then indentifies herself as "Vicki" from [some name], which is where "your father works."

Vicki then tells you that "Your father was taken to [some hospital name] at 10 o'clock this morning, and we are trying to reach your mother."

That type of phone call certainly gets your attention, no matter how little sleep you've had.

Not to worry, my dad is okay. It boils down to the fact that he's a workaholic (no, really) and he's getting older.