David Tennant told his son Ty to "always be on time".
David and Ty Tennant
The 'Doctor Who' star's adopted son is making his feature film debut in 'Tolkien' - in which he will play a young Christopher Wiseman - and he has turned to his famous father to get advice on his fledgling acting career.
Speaking to the MailOnline at the movie's premiere at Curzon Mayfair in London on Monday (29.04.19) about the tips he received, Ty said: "Never be late. Always be on time.
"Don't skip the lunch queue so you don't look like a bit of an idiot, and just be kind and friendly and know your lines."
The teenager - whose mother Georgia Moffett married David, 48, in 2011 - admitted he was taking on advice from anyone who could help him, and he was grateful to ply his craft on screen alongside the likes of Nicholas Hoult and Lily Collins in the new J.R.R. Tolkien biographical drama.
He added: "I got tips from everyone. I'm so young in my career and I'm still learning a lot and I'm so lucky to have these people around me who know the industry very well.
"And they're just very inspirational so that's something I can really thrive on. Just having these people who know their stuff."
Meanwhile, David has three children with Georgia, who gave birth to Tyler in 2002 when she was just 17 and has never publicly revealed the identity of his biological father after raising him alone.
Together, the loved up couple are parents to Olive, eight, Wilfred, five, and four-year-old Doris.
Speaking after adopting Ty, the 'Broadchurch' actor joked he may have broken "some kind of record".
He quipped: "My baby is almost a year old and I adopted my wife's boy last year as well so I became a father twice in six months - that's got to be something of a record hasn't it?"
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