David Tennant's eldest son lectured his parents after he found out they were expecting baby number five

Ty Tennant gave his parents a quick lecture!

Emmy Griffiths

David Tennant has opened up about expecting his fifth child with his wife, Georgia. The Good Omens star visited The Graham Norton Show, and opened up the happy news, and his eldest son's hilarious reaction. He said: "We have number five child on the way. It's very exciting. There is a big spread of ages, with a 17 year old at one end. When he found out about the new baby, he was like, 'You're having another one?' It's odd when a 17 year old is giving his parents a lecture on birth control!"

David Tennant opened up about expecting baby number 5

David and Georgia currently share four children, Ty, 17, Olive, eight, Wilfred six, and Doris, four. James Corden announced the exciting news in late May on The Late Late Show, saying: "We were just talking backstage, this is blowing my mind. You have four children already, your oldest is 17. You just told me you and your wife, the lovely Georgia, are expecting your fifth child." David replied: "What's really weird about it is we're now getting lectures on birth control from our 17-year-old son. And that's definitely meant to be the other way around. He's like 'Come on, do I need to teach you the basics?' It's mental. It's a lot."

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David is currently starring in Good Omens

David and Georgia – whose dad, Peter Davison, was the fifth actor to portray the famous Time Lord between 1981 and 1984 – met when she starred alongside him in the Doctor Who episode, The Doctor's Daughter, in 2008. David usually keeps his private life behind closed doors, but once opened up about his marriage to the Guardian after the journalist joked that it was as if he'd deliberately picked a partner who was the daughter of a Doctor, he responded: "That's exactly what I did, yes, and there were very few candidates available. It was a limited field."

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