"I bet," he agrees, his attention having shifted entirely away from comedy interstitials featuring the crew of the Satellite of Love. The movie's background noise, an excuse to hold Scully and mumble stupid conversations and maybe kiss her. "Let's hope William inherits your ability to fall asleep. It's going to be a rough time otherwise."

Will he even have to deal with that? Imagine Scully with an insomniac baby, woken repeatedly out of a dead sleep by cries of boredom - and Mulder living half an hour away, unaware that his late-night restlessness is playing havoc in a new generation. Moving closer wouldn't help. Moving in would blow their cover.

It's a strange feeling, to realize just how much distance comes with the title of Secret Father Of A Child.