Ok, new headcanon. Rory is a big fan of Sir Terry Pratchett. Everytime River visits her parents he reads her Where’s my cow?, because he wanted to read it to his child.
I love this!
#IS THAT MY COW? #IT GOES ‘EXTERMINATE!’ #IT IS A DALEK. #THAT IS NOT MY COW!
It goes “Exterminate!” It’s not my cow.
WAIT WHAT I NEED PROOF SHOW ME THE PROOF!!!