'That's really sad if it's that unusual!': Kate Beckinsale admits she is 'basically family' with her ex Michael Sheen and his new girlfriend Sarah Silverman

They were in an eight-year relationship and raise 17-year-old daughter Lily together.

And Kate Beckinsale has revealed she's 'basically family' with her ex Michael Sheen and his new girlfriend Sarah Silverman, who she invited to the premiere of her new movie Love and Friendship earlier this month.

The 42-year-old actress can't understand why people are surprised they're so close and finds it 'really sad' that their friendship is considered unusual.

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Three's certainly not a crowd! Kate Beckinsale has revealed she's 'basically family' with her ex Michael Sheen and his new girlfriend Sarah Silverman, who she invited to the premiere of her new movie Love and Friendship earlier this month

Three's certainly not a crowd! Kate Beckinsale has revealed she's 'basically family' with her ex Michael Sheen and his new girlfriend Sarah Silverman, who she invited to the premiere of her new movie Love and Friendship earlier this month

She told Stylist magazine: 'I don't know why everyone was so surprised. Sarah's such a fantastic woman, I love her and Michael and I have gotten on for years now. I've known him since I was 22, we're basically family.

'The thing that surprised me was what a big deal everybody made about us all getting on and then thinking, "F**k, that's really sad if it's that unusual.

Kate also revealed that comedienne Sarah is a great influence on Lily and says she would want her around her daughter even if she were no longer dating the Masters of Sex star.

Close bond: Kate and Michael recreated the moment they cradled daughter Lily, 17, for the first time in a silly Instagram post on Wednesday, proving how close she still is to ex Michael

Close bond: Kate and Michael recreated the moment they cradled daughter Lily, 17, for the first time in a silly Instagram post on Wednesday, proving how close she still is to ex Michael

She added: 'I'm completely open to any other strong, cool sensitive independent-thinking women who are going to be an influence in my daughter's life.'

The Underworld actress, who has a joint honours degree in French and Russian literature from the prestigious Oxford University, and would love to go back to university to study more.

But for the meantime, she wants to focus on helping Lily pursue higher education.

Kate's candid comments come after she cosied up to Michael and Sarah at the Los Angeles premiere of her new film.

She's a fan: Kate also revealed that comedienne Sarah is a great influence on Lily and says she would want her around her daughter even if she were no longer dating the Masters of Sex star

She's a fan: Kate also revealed that comedienne Sarah is a great influence on Lily and says she would want her around her daughter even if she were no longer dating the Masters of Sex star

Best of friends: Sarah has been equally complimentary about Kate in the past, having previously said: 'I love her. She's hilarious... She's really really cool. They're really funny together'
Best of friends: Sarah has been equally complimentary about Kate in the past, having previously said: 'I love her. She's hilarious... She's really really cool. They're really funny together'

Best of friends: Sarah has been equally complimentary about Kate in the past, having previously said: 'I love her. She's hilarious... She's really really cool. They're really funny together' 

Speaking to E! on the red carpet, Kate admitted she was thrilled at Michael's choice of girlfriend.

She said: 'I love her. I love her. I love her. I am so glad Michael found her so I don't have to spend the rest of my life looking for her.'

Sarah has been equally complimentary about Kate in the past, having previously said: 'I love her. She's hilarious... She's really really cool. They're really funny together.'

Kate, who is said to have split from director husband Len Wiseman, was in a relationship with Michael from 1995 until 2003, although they never married.

Michael has been dating Sarah since early 2014, a year after his split from Canadian actress Rachel McAdams after two years together.

Back in the day: Kate, who is said to have split from director husband Len Wiseman, was in a relationship with Michael from 1995 until 2003

Back in the day: Kate, who is said to have split from director husband Len Wiseman, was in a relationship with Michael from 1995 until 2003

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