But things didn't start out as smoothly between the pair as you might think, as the Big Little Lies actress previously confessed.
Nicole - who married the love of her life in 2006 - told Ellen DeGeneres back in 2017 that after giving Keith her number, he didn't call her for months, leading to her assumption that he wasn't interested in her.
"I remember thinking, I had such a crush on him, and he wasn't interested in me. It's true! He didn’t call me for four months," she explained. Keith had his own take on the story, telling talk show Interview in 2018 that he had been thinking long and hard about what to say if he called Nicole, as he wasn't in a great place in his life back then.
"Somebody had given me her number, and I had it in my pocket for a while," he said.
"I kept looking at it thinking, 'If I call this number, she's going to answer. I don't know what [to] say.' I wasn't in a very healthy place in my life … I'd never have thought she'd see anything in a guy like me.
"But, at some point, I plucked up the courage to [dial] those numbers and she answered, and we started talking. And we talked and talked and talked and talked, and it was effortless."
The pair had met at the G'Day USA Gala in 2005, which is an event honoring Australians in Los Angeles. What's more, they were so loved up the following year, that they got engaged.
The Hollywood star announced their engagement in May 2006 while hosting the 30th Anniversary gala for the organization UNIFEM, the United Nations Development Fund for Women.
"He's actually my fiancé. I wouldn't be bringing my boyfriend, she told reporters on the night. The supportive couple - who went on to welcome two daughters - Sunday, now 15, and Faith, now 12 - are known to share their workload between them so that one of them is always around for their children at home.
When they do end up going on the road for a long period of time, they join each other as a family too. While they are protective of their daughters' privacy,
Sunday and Faith have shown interest in following their moms' footsteps in the acting industry, having appeared in a number of her projects as extras, including The Undoing and Big Little Lies.
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