Nicole Kidman has a fear of butterflies.

Nicole Kidman

Nicole Kidman

The 49-year-old actress is thought to suffer from lepidopterophobia, which is a fear of the flying insects.

Taking part in a quiz about her 'Big Little Lies' co-star, Reese Witherspoon was asked to pick which of the two statements - Nicole's high school nickname was 'Legs' and Nicole is deathly afraid of butterflies - she thought was true.

She told Entertainment Tonight: "She's not afraid of butterflies. I agree that she was probably called 'Legs.' Am I wrong?"

To which the interviewer replied: "She suffers from lepidopterophobia - a fear of butterflies. And her high school name was 'Stalky.'"

And although she didn't know about Nicole's big fear, Reese has "always looked up" to the 'Lion' star .

She said: "We didn't know each other very well before we started but I just always ... I always looked up to you. You're such an incredible actress."

And Nicole replied: "I call myself your big sister now ... I'd never had the experience of working with another woman so closely that I got to call you and say, 'What do you think I should do with this character? I don't like this scene and I don't know how to play this."

And Reese previously confessed she has become "deeply invested" in her 'Big Little Lies' co-stars.

She shared: "We talked about nothing to do with work. It was always just our personal lives: what's going on with our kids, single girls and who they're dating. We just became a really close-knit family, even with the kids, too - hanging out with them and playing with them.

"You get deeply invested in people. I think that's part of the experience of getting to know people. What deepens our relationships on set, even more than a rehearsal, is the glass of wine you have after work. 'What's on in your life? How's your mom? How's your heart?' That kind of stuff."

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