While the Impossible star admits her husband and fellow actor Liev Schreiber is a "brilliant dad" to their children, Sasha, five, and four-year-old Sammy Kai, and the quartet have a "good" family life, she admits they also have their "struggles".
She said: "Our family life is good, Liev is a brilliant dad, but like any family we have had our struggles and a relationship between two successful people who travel and are passionate about what they do takes work - it's not all a bed of roses."
But the 44-year-old star insists that she and Liev, 45, still "hold onto our romance", and she would love to add a daughter to their family unit in the future.
She added to You magazine: "I would love a daughter and it would be great to adopt but I kind of feel that my boys are finally getting on so well - so is it the right time?
"Liev is great - we still hold on to our romance. It was love at first sight for me. In fact I had a big crush on him before I met him at a ball.
"We had friends who had been trying to set us up for ages, but it was never the right time until that night. We exchanged numbers - I was in LA at the time and he was in New York - and at first we got to know each other through emails and phone calls."