Gwyneth Paltrow "doesn't know" how to be a stepmother

Gwyneth - who has Apple, 14, and Moses, 12, with ex-husband Chris Martin - told WSJ magazine: "We are still doing it in our own way. With teenage kids, you've got to tread lightly. It's pretty intense, the teenage thing. I've never been a stepmother before. I don't know how to do it."

But the 46-year-old star admitted her second marriage is "fantastic" and she feels she was in a better position to find her "life partner" than when she married the Coldplay frontman in December 2003.

She said: "It's fantastic. I feel like we are probably better equipped to choose our life partner when we are halfway through life. But generally, we have to pick our spouses a lot earlier because of the whole procreation piece.

"For me it has been more of a process, and so I feel really lucky to have met this person who is an incredible, true partner."

The Goop founder also claimed she and her friend Cameron Diaz "cry with gratitude" that paparazzi culture didn't exist when they were younger, and she's thankful she was able to go about her business without being bothered after her high-profile break-up from Brad Pitt in 1997.

She said: "Cameron Diaz and I talk about this all the time. We're like, 'Thank God in the early '90s there were [so few] paparazzi. Thank God.' We cry in gratitude that no one was following us around and seeing what we were doing.

"I remember when Brad Pitt and I broke up, it was on the cover of the New York Post and there was no one outside my house. That would never happen today."