David Tennant's son Ty makes debut on Casualty

Mother Georgia, who also starred on Casualty, posted on Twitter after the episode had aired to celebrate.

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"I am so proud of Ty Tennant tonight on BBC1's Casualty," she posted on Twitter. "He was so good they didn't feel the need to crush him to death in a lift shaft..."

Georgia's character Heather Whitefield met an unfortunate event in her second episode of Casualty in 2009 when she was trapped beneath a burning lift. She later returned to the soap as a different character for a guest role in 2014.

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This isn't Ty's only screen credit this week: he is also been part of the cast of the newly released Tolkien biopic.

Ty was joined by his his Dad, former Doctor Who star David Tennant, for the premiere of the new film in London.

The family already have an impressive Doctor Who acting heritage: Ty's grandfather is Fifth Doctor Peter Davison, while Georgia guest starred with future husband David in 2008 episode The Doctor's Daughter.

In Casualty, Ty plays Aaron, the teenage son of a man who suffered a broken neck after falling from a ladder. Admitted to hospital following a seizure on his birthday, the truth about their family plays out over the course of the episode. The episode is available to watch on iPlayer now.

Ty has also been working on the upcoming BBC adaptation of War of the Worlds, set to air later in 2019.

David Tennant meanwhile is set to star in the upcoming adaptation of fantasy novel Good Omens on Amazon.