David Tennant thought it felt "a bit stupid" to marry the daughter of another Doctor Who actor.
He wed Georgia Tennant, the daughter of fifth doctor Peter Davison, in 2011 and the pair share five children.
The couple spoke about their relationship on The Gaby Roslin Podcast where Georgia, 35, said she was the "driving force" in the pair getting together.
“You couldn’t quite believe that’s why I was messaging you 400 times a day.
“You thought maybe I was lonely and wanted a chat… I very much fell into stalker category. Thank goodness I did though. I just made a decision, I thought, ‘This is going to be good, let’s do this, I’ll just persevere until he gives in,'" she shared.
David, 49, remarked: “I thought we were an unlikely life partnership, there was a bit of an age gap.
“Because Doctor Who had run through my life like a stick of rock, to end up marrying the daughter of one of the doctors, it all felt a bit stupid… so there were a lot of things against it.”
The Scottish actor played the Time Lord from 2005 to 2010 while his father-in-law was in the role from 1982 until 1984.
Georgia met her husband when she played opposite David's Doctor in 2008 episode The Doctor's Daughter as the character's artificially-created offspring.
She has a son from a previous relationship, Ty, who has since been adopted by David.
Together they also have four more children, son Wilfred, seven, daughters Olive, nine, Doris, five, and Birdie, who recently celebrated her first birthday.
While David and Georgia had long chosen not to speak about their family in public, he recently shared they now felt "less squeamish" about protecting their privacy so rigidly.
"I don’t think we’ll ever be sharing pictures of our children in Hello! magazine, but I think a lot of that comes from an insecurity about being uncovered or invaded. The longer you’re together, the less that feels like a threat,” he said.
Watch: David Tennant talks his Doctor Who role