Zoe Saldana "cried every day" when she returned to work after having twins.
The Star Trek star admits she got emotional when she first went back to a film set following the birth of her 20-month-old kids Cy and Bowie.
She said: "The first week back at work, I think I cried every day in my trailer. But I remember as soon as they would tell me 'We're ready for you on set,' I would still skip to set. I love what I do. You do need to rest, you do need to have a moment to yourself, but right now this is my life as I know it.
"They're 20 months old, and they're starting to feel my absence. They still don't really have an accurate concept of time, but they're becoming a little anxious. And that's when you ask people, you ask a therapist 'Is this normal?' You read books, you go on Google ... But I always explain to them that I come and I go, but Mama has to work. I also make sure that they see me happy when they come visit me at work - they need me to lead by example."
And the 38-year-old actress - who has her two children with husband Marco Perego - went on to praise Simon Pegg and Doug Jung for allowing her to ease back into filming slowly.
She added to PEOPLE magazine: "I remember telling [writers Simon Pegg and Doug Jung] that I did not want to be a part of anything 'stunt-y' because my body was still trying to get back into shape and organs were trying to get back into their natural position.
"You're not as sturdy as you believe yourself to be and I wanted to give my body time. I didn't want to force myself into anything. They were like 'Oh my God, absolutely.'"
- Bang! Showbiz