Gwyneth Paltrow says Stella McCartney is "a bit naughty".
The 40-year-old actress described the fashion designer as her "sister" in an emotional post in her lifestyle newsletter Goop in which she also claimed the pair share "similar values".
She wrote: "Sometimes in life you get a girlfriend who becomes like a sister. Someone who really sees you. Who is as honest with you as they are loving. Who shares a similar world view, who has similar values.
"Who is a bit of a life raft when you live in a country that you lovingly adopt, but is not your own. Who also happens to be hilarious and a bit naughty and is constantly trying to get the balance of everything right, just like you are.
"Who is also one of your favorite designers ever, who has a ruthless eye and makes perfect, perfect things. Stella is that girl and so much more."
In the post, Gwyneth also revealed they had paired up on a "very mini" collection which featured black and navy jeans and a black wool blaze, among other items.
She continued: "I convinced her to do a collaboration, a very mini capsule collection of some beautiful, covetable things."
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