When you watched "What a Night, for a Dark Knight!" from Guess Who, did you think it was really stupid how they had Alfred Pennyworth be Daphne's uncle? So did I, at first, but this was actually an incredibly clever reference on the writers' part.
In the 1970 version of the Batman DC Comics, Alfred actually did have a niece named Daphne. As you can see, the panel in which this occurs in the 1970s comics is pictured above.