Rachel Weisz has admitted it is hard to balance being a mother with travelling the world making movies.
The actress - who is married to James Bond star Daniel Craig - is mother to six-year-old son Henry, from her relationship with director Darren Aronofsky.
Rachel said: "Of course it is difficult, but it is difficult for any working mother. All mums face the challenge. I am lucky that I work extensively and then I am off. Some mums work all day and they get home late and have to be a mum."
The actress - who stars with Jeremy Renner in espionage thriller The Bourne Legacy - revealed she had been practising her interrogation skills at home with her son.
She said: "For my son's birthday, he just got this little plastic lie detector test. He makes me put my fingers on it, and he asks me questions. I turn it around on him and ask questions like, 'Did you eat your vegetables at school today?' It has been fun."
::The Bourne Legacy is released on DVD on Monday December 3, 2012.