The couple dated for eight years before its split in 2003, but the actors have remained close for the sake of their only child, 17-year-old Lily, and frequently spend time together with friends and relatives as one big happy family.

Kate admits she is lucky to have such a great relationship with her ex, but the key to their continued friendship is doing what's best for their little girl.

Asked what the secret to their close bond is, Kate quips to Entertainment Tonight, "Well, one, pick well! And two, I think we both really felt like, we really agreed on what would be the right thing for Lily. I think, you know, not hating each other (is key) and fighting and all that would be awful for her."

But Kate insists laughing their way through life's ups and downs has always helped the pair deal with any issues.

"I think we've also got a really similar sense of humour, and I do find that humour can save an awful lot of things and help a lot of things," she adds. "I just really like him. He's family. I've known him since I was 21, so he's proper family now."

Kate has also become known for hanging out with Michael and his girlfriend, comedienne Sarah Silverman, who she previously admitted she was a big fan of.

The Underworld star, who split from her director husband Len Wiseman last year (15), is planning to spend the festive season with Lily, Michael and Sarah, as has become custom, and getting together every holiday ensures the celebrity parents never miss out on quality time with their kid.

The 43-year-old continues, "We had Thanksgiving at his girlfriend's house and they're having Christmas at our house. We like hanging out with each other, so it's not like, 'Oh, who gets Lily?' or whatever. It's like, 'Whose house are we going to be at?'"