Does it ever bug you when other people are awake when you are?

Over the years, I’ve developed the habit of staying up late to work, surf the web, play games, etc., partly because I wouldn’t be disturbed, partly because I don’t sleep well. I got a lot more free time once I graduated, but I still enjoy and maintain the habit.
Recently my dad’s been having bouts of insomnia, so now we’re both up at uncivilized hours. The more rational part of me takes no issue with his wakefulness, and even sympathizes some. But the unkinder portions get irritated that I’m not the only one awake.