With Fox as a surname, the odd pun is somewhat of a given.

But ‘cunning as a fox’ and ‘sly old fox’ were too bland for the Silent Witness crew when it came to marking actor Emilia Fox’s upcoming 10th year as Dr Nikki Alexander in the long-running BBC drama.

"Very kindly, my colleagues Richard, David and Liz and the whole crew put together a very funny music video of Ylvis's What Does The Fox Say? and dressed up as animals," she laughs. "They played it at the wrap party. It was the sweetest, most touching thing."

Fox is just as fond of the "great team" as they are of her, especially given how accommodating they’ve been since she became a mother to daughter Rose three years ago from a previous relationship with fellow actor Jeremy Gilley.

"I’m incredibly grateful to Silent Witness, who’ve been there pre-Rose, being pregnant with Rose and having Rose," says Emilia. "The studio filming’s done five minutes away from my house, so I’ve always been able to have her at work or go home and see her.

"That’s made things much easier. It would have been much more difficult if I had to do all of those things away from home."

The question of balancing parenthood with a career is one very much on the 39-year-old’s mind at the moment: for the first time in years, she’s returning to the stage in a production of Rapture, Blister, Burn at Hampstead Theatre - a play about two women who’ve gone down very different paths in life. One’s a high-flying academic while the other’s built a happy life at home, but both envy the other’s choices.

"Where we’ve got to is quite rightly women having equal opportunities," says Emilia. "The play’s left me burning to discuss the issue of ‘having it all’.

"But where the problem comes with that is trying to juggle professional life, domestic life, children and relationships and how to balance it and make it possible to have that balance.

"And does everyone want to have that? Not necessarily. Some people don’t. Some people are satisfied with having one of those things and that's absolutely right."

At face value, it would seem that Emilia is a shining example of someone who has struck a good balance between work and parenthood - and retained her privacy.

She was in a relationship with celebrity chef Marco Pierre White that recently ended and is divorced from Mad Men actor Jared Harris (son of Richard Harris), but the daughter of actors Joanna David and Edward Fox isn’t the type to kiss and tell.

"You have a professional life and you have a private life and I think that’s all-important, and my private life is only Rose and mine's."

Emilia’s acting dynasty family also includes brother Freddie, uncle James and cousin Laurence, who’s married to actress Billie Piper.

Emilia studied English literature at Oxford University and made her TV debut with a role in the much-loved 1995 TV mini-series of Pride and Prejudice, as Colin Firth’s sister, alongside her mum, who played kindly Mrs Gardiner. Since then, she’s appeared in the likes of Merlin and, last year, The Wrong Mans, alongside James Corden.

Now she’s fully established, she’d be delighted to be reunited on screen with her mother, best-known for roles in War and Peace, Rebecca and more recently as the Duchess of Yeovil, an old pal of the Dowager Countess, in Downton Abbey.

"I would love to work with mum. She's the actress I most look up to, I think she's the most truthful actress," says Fox.

Now she’s a mum herself, she admits she’s in awe of the way her parents raised their brood.

"I had such a lovely upbringing by my parents," she says. "I have amazing, loving, very secure-making parents, and that’s what I'd like to pass on to Rose."

  • Rapture, Blister, Burn is at Hampstead Theatre, Eton Avenue, Swiss Cottage from January 16 to February 22. Details: 020 7722 9301, hampsteadtheatre.com