Cara Delevingne is so close to her sisters that she jokes she'd help cover up a murder for them.

The model turned actress is the youngest of the Delevingne clan and enjoys a close relationship with her siblings Poppy, 30, and Chloe, 32.

Growing up the trio had plenty of hardships to deal with, with Chloe and Poppy often acting as the parent figure to Cara as their mother Pandora battled depression and an addiction to heroin.

"We have been through everything together. They helped bring me up," Cara told Porter magazine. "They taught me my love of music. We used to do dance routines to the Spice Girls, which we still do.

"I wouldn't ever want to imagine a world without Poppy and Chloe. Put it this way, if one of them killed someone I would help bury the body."

Cara, 24, was joined her sisters for the interview, with all three posing for the accompanying photoshoot.

The subject of Pandora's drug battle has never been secret, with the matriarch opening up about her demons in the past. Poppy adds she's never felt anger towards her mom as addiction and mental illness is a sickness, but she admits times were tough when she was younger.

"There were tricky times. I was 12 when it all started happening, which is the time you really need a mom - getting your period, wanting to know what sex is about," she sighed. "Cara was six years younger. She slept in my bed for years. She would literally twine her body around mine when I tried to sleep. To have each other was just so, so vital."

Poppy, who also works as a model, is now following Cara into acting. She's landed a part in Guy Ritchie's King Arthur: Legend of the Sword and admits she calls on her younger sister when she needs help "hustling" in Hollywood.