you have to qualify things like that
Doctor Who is the longest-running science-fiction television series of all known time.
…of all known time. All known time?! Is there a science-fiction television series that existed before written history? Or are we including other universes? Alternate timelines?
(from the BBC America Shop)
Doctor Who Confidential: Series 4 - The Doctor’s Daughter
David: Peter Davison is Georgia’s dad. There is a… clearly a very strong Doctor Who link there.
Peter: She rang me up I remember she said: “Can I tell you my first line?” And I said yeah, go on then, “It’s ‘Hello, Dad!” [laughing]
Georgia: The first line was “Hello Dad” and I was like Oh my God.