So how the Doctor is going to feel this week when he finds his daughter doing just that?
And how much continuity are we going to get? Any mentions of Susan and Gallifrey, for instance?
Family mentions in Doctor Who have been rare - we have to go back to the Troughton era for the last original run example, while Marc Platt's Ghost Light was originally going to be the story that became the novel Lungbarrow and set on Gallifrey in the Doctor's family home. Had it been made, genetically loomed Time Lords would have become series lore...
Similarly, it is now confirmed that the Master and the Doctor are not brothers; yet the Doctor has referred to other family several times since 2005's season 27.
Of course the main question about this weeks adventure is this: is Jenny really The Doctor's Daughter?