Well they were married for quite a long time. Matt Smith has told fans at New Orleans Comic Con that he asked Steven Moffat not to write scenes between River and Peter Capaldi’s Twelfth Doctor, reports DoctorWhoTV.
“Don’t ask. I’m really possessive over Alex,” said Matt “I said this to Steven. I was like, ‘Listen, just don’t! Just not Alex. Anyone else, but don’t give [Capaldi] River.’ But Peter is the Doctor now so hey, what can I do?”
He added: “I think that Steven will be planning things that are going to unfold over years and I think he’ll reinvent the folklore, and it will become Peter’s folklore. But I am really proud of the fact that Alex was part of number Eleven’s life. My wife!”
Steven Moffat is still uncertain on whether he’ll bring back River Song.
“It’s always down to whether there’s a good story. My immediate instinct was that story’s probably done,” said Steven “Not that we saw all of it, but I never thought we should see all of it. I’m slightly tempted, because I imagine Peter Capaldi and Alex Kingston would be absolutely hilarious together…She could certainly have met other Doctors. So there’s nothing stopping us…But is there anything new we can do? Or is the new thing that Peter Capaldi and Alex Kingston would be very sexy together? Is that enough? We’ve always had fun with the fact that they don’t look like a couple.”
“Peter Capaldi and Alex Kingston would look like a couple – that’s the thing,” he added “Whereas I thought Matt and Alex were gorgeous together, but it looked slightly strange, because he was so much younger. Alex is just great fun to have on the show. It’s when you want to throw the Doctor a bit, because what River does so well is to make him a bit on the back foot and a bit flustered.”