whats this about the doctors granddaughter whiteman?
Whenever the show first came on television in the sixties, The Doctor was an old fart and he was accompanied by his granddaughter Susan Foreman (I'm assuming that they just stapled the last name on since that was the junkyard where they were originally hiding the TARDIS at the beginning of the show) and two of her schoolteachers: Barbara Wright, who was a history teacher, and Ian Chesterson, who was a science teacher. The show was originally slated to be educational, which is why those specific teachers were chosen.
The first episode (and what they call the four episode serial now) is called "An Unearthly Child" referring obviously to the fact that Susan is a Time Lord. Whether Susan was an adopted granddaughter or by relation is unknown.
Therefore, the notion of the Doctor having a daughter isn't ridiculous at all. For all we know, the Doctor has had several children. I mean, he's been alive for 900 years plus. Thirty years of television, obviously, hasn't begun to reveal all of the secrets of the Doctor.