David Tennant is going to get married to daughter of former Doctor Who...

... who also, in a very complicated way also played Doctor Who, causing thus the (geek girls) universe to explode.

The only accepted time to start a sentence with "I'm a doctor" is when you'r Doctor Who (or someone is dying) 

This is going to get complicated, so bear with me!
David Tennant, the Tenth Doctor, is going to marry Georgia Moffet, who is the daughter of Peter Davidson, who was the Fifth Doctor. Nice, isn't it? But no, it gets messier!

"Will she have time for him? Ask various geek girls, just to be slapped silly for the bad pun"

She also played the Doctor's daughter, which was a clone of the Doctor, making her sort of 10 and 1/2 Doctor.
Bonus round, anyone can name who her mother is and what made her (geek) famous? Leave it in the comments and win geek cred.