David Tennant (10th Doctor) married Georgia Moffett (the 10th Doctor’s daughter in the episode “The Doctor’s Daughter”), who is the daughter of Peter Davison (5th Doctor) and they had a daughter. So the Doctor’s daughter played the Doctor’s daughter in “The Doctor’s Daughter” and then married the Doctor and had the Doctor’s daughter.
I got lost at Doctor
This just sounds like a regular episode.
^ regular episode
Doctor Who everyone.