“Cameron was very excited about Gwyneth’s wedding,” a source previously PEOPLE. “Gwyneth has been giving her updates and asking for advice during the planning.”
“Cameron pulled off a private wedding even though the media found out about it before. Gwyneth wanted the same privacy,” the insider added, explaining what kind of expertise Diaz brought to the table.
Of course, The Other Woman star was also on hand to celebrate her friend’s big day, and attended the private Hamptons ceremony alongside her husband Benji Madden.
Here’s a look back at their enduring friendship.
Bonding Through Heartbreak
During an interview with Harper’s Bazaar U.K. in 2012, Diaz revealed that the pair first “became very close” following the death of her father, Emilio Diaz, in 2008.
“She reached out after my dad’s death,” Diaz told the magazine, according to E! News. “It was very sweet. We bonded on that.”
Paltrow lost her father, Bruce Paltrow, in 2002.
Shared Commitment to Wellness
Over the years, the pair have both become outspoken advocates for wellness, yoga, and healthy eating.
While praising Paltrow’s 2016 book, It’s All Easy, Diaz wrote, “the easiest thing on earth to do is LOVE this woman and her cooking.”
“She is the epitome of a nurturer…she cooks with her heart and soul…and it is guaranteed that every meal, dish, snack, even whisper of a recipe that she creates will feed yours…it is her essence to share and to include. That’s why it makes sense that her new cookbook #ItsAllEasy shows you that you can actually cook those meals you always wish you had the time for…and not only will it be all easy I promise you that it will also be DELICIOUS, HEALTHY and NOURISHING,” she continued.
Diaz, who was a guest at Paltrow’s annual Goop Health wellness summit over the summer, has also penned two books centered around wellness: The Body Book and The Longevity Book.
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Over the years, Paltrow has also penned many glowing birthday messages for her pal, whom she describes as her best friend.
“Happy birthday @camerondiaz Your wisdom, humor, loyalty, cooking skills, guffaws, and ice cubes in rose get me through my life,” she wrote in 2017, alongside a selfie of the pair cuddling up together. “I adore you with all my [heart] (And yes, we are wearing bibs in this picture).”
The previous year, she also wrote, “I hit the ground with gratitude for getting to be one of the women who calls you a best friend.”
Hair and Makeup Help
Before turning to her pal to help make her wedding the best it could be, Paltrow revealed that she turns to Diaz for tips and advice on makeup and hair styles.
“Cameron Diaz is probably my biggest beauty mentor of my friends,” the actress told Elle in 2016.. “She knows how to do her own hair and makeup; she’s really good at it. And she was the one who really taught me how to do my own hair and makeup back in the day so she’s my biggest beauty mentor.”
While Paltrow went on to add that her friend has given her “lots of tips” over the years, “I can’t remember them off the top of my head.”