VASTRA: But could the child have begun on the TARDIS in flight, in the vortex?

DOCTOR: No! No! Impossible! It's all running about, sexy fish vampires and blowing up stuff. And Rory wasn't even there at the beginning. Then he was dead, then he didn't exist, then he was plastic. Then I had to reboot the whole universe. Long story. So, technically the first time they were on the TARDIS together in this version of reality, was on their w-

VASTRA: On their what?

DOCTOR: On their wedding night.