Gwyneth Paltrow used to have a "difficult relationship" with her stepchildren.

The 51-year-old actress has Apple, 19, and Moses, 17, with ex-husband Chris Martin, but became a stepmother to Brody, 17, and 20-year-old Isabella when she married TV producer Brad Falchuk in 2018, admitted that she even though she now thinks of them as her own, she had to "learn" a lot in the early days.

Speaking at the Visionary Women's International Women’s Day Summit, she said: "Yeah, it's a b****, right, guys? No, I actually, I really like to talk about this because it's one of my biggest learnings as a human being. And my area of growth personally came from the initial difficult relationship I had with my stepkids and now they're like my kids.

"The path to here was really rough. it's almost like you have to embody the spirit of the sun and just give and not expect anything back. I just learned to try to just keep shining like the sun and never keeping score."

The Goop founder was joined by political activist Nicole Avant, who married Netflix CEO Ted Santos and became stepmom to his children Sarah and Tony, during the event, who admitted that when she became a stepmother herself, she had to constantly find her "own identity" because she was trying to me their mom as well as a girlfriend to their father.

READ MORE: Gwyneth Paltrow Through the Years: 40 Times the Star Looked Flawless (PHOTOS)

She said: "It was constantly me having to find and own my identity over and over and over again. I kept feeling that my identity was being challenged every single day and I wasn't trying to be their mom, but all of a sudden I was the girlfriend that they loved and they wanted their father to marry.

"[At times], it was heartbreaking."

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