Sadie Frost relied on her sister during the "tough" breakdown of her marriage to Jude Law.
The 49-year-old designer has admitted that her divorce from the 'Sherlock Holmes' actor in 2003 was "tough" but thanks to her "caring and loyal" half-sister Holly Davidson she got through it.
Talking in The Sunday Times magazine, Sadie shared: "My marriage breakdown was also tough and [Holly] was so caring and loyal, in fact, she has always been there for me, she's very good with relationship advice."
Holly then added: "When Sadie's marriage to Jude ended, it was just heartbreaking. Seeing her in so much pain was the most heart-wrenching thing ever. She was not in a good space.
"There were phone calls into the night. And while I'm a fixer, with this there was nothing I could fix."
The 34-year-old fitness trainer also helped her older sister battle postnatal depression after Sadie gave birth to her son, Rudy in 2002.
She told the magazine: "[Sadie] didn't tell me at first that she was unhappy, but I could see it. Part of me wanted to say something, but I didn't know what to say. I just tried to be there for her until she could be more open about it."
Sadie revealed that it was a "relief" to tell her sister that she was suffering from postnatal depression but admitted that she'd felt "guilty" about feeling so low.
She shared: "When you have everything - a beautiful husband, a beautiful house, a career, kids - and you still have this awful depression, there's a huge amount of guilt."
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