From Paris Hilton's best mate to reality TV queen: Here's what Nicole Richie's life looks like now.

Once upon a time, four years before the juggernaut that is Keeping Up with the Kardashians burst onto our screens, there was a little ol’ reality TV show called The Simple Life.

Most Millennials will remember it well.

Everyone’s fave spoiled socialites, BFFs Paris Hilton and Nicole Richie (adopted daughter of Lionel Richie) were stripped of their wealth and their flip-phones, sent out into rural America and forced to live… a simpler life.

As the girls got their heads around things like farming and asked questions such as “what is Wal-Mart? Does is sell wall stuff?” hilarity obviously ensued.

The Simple Life became a staple of 2000s pop culture, making Hilton and Richie household names.

But while Hilton still makes headlines (admittedly, not quite to the same extent as her other BFF Kim Kardashian), Richie has been a bit quieter the past few years.

So we did a little deep dive to find out what she’s been up to since The Simple Life.

Falling out with Paris. 

The Simple Life was a huge hit when the first season dropped on MTV in 2003. It was renewed for a second and a third season, but according to PopSugar, production on the fourth season was halted due to a dispute between Hilton and Richie.

PopSugar reports that Hilton confirmed the pair were no longer friends: “It’s no big secret that Nicole and I are no longer friends. Nicole knows what she did, and that’s all I’m ever going to say about it.”

Meanwhile, Richie told the Today Show that the friends had simply ‘grown apart’. She denied a feud, saying that the incident had “just turned into a much bigger thing than it is. It’s just not part of my life.”

Nicole and Paris were BFFs until they fell out for unknown reasons. Image: Getty. 

She also denied rumours that Hilton was to go ahead with filming the fourth season of the Simple Life, replacing her with Kimberly Stewart.

"That was never going to happen," she said.

Eventually the pair managed to muddle through their differences and the fourth season went ahead.

But it was during production for the fifth season that trouble started...

Controversies.

During filming of the fifth season both Hilton and Richie were arrested and charged with DUI, in separate incidents. Richie's involved her driving the wrong way on the freeway while under the influence of drugs. She pleaded guilty and was sentenced to 90 days in prison and fined $2048 (US). She ended up serving just 82 hours before being released due to overcrowding.

Meanwhile, Hilton, who'd failed a breathalyser after being stopped on her way to In-N-Out Burger (which she later blamed on having one margarita on an empty stomach), was sentenced to three years' probation.

It was around this time that concern grew for Richie due to her dramatic weight loss. In an interview with Vanity Fair, the star denied having an eating disorder but acknowledged that she was "too thin".

She told the magazine: "I know I’m too thin right now, so I wouldn’t want any young girl looking at me and saying, ‘That’s what I want to look like.'

Marriage and kids.

Richie began dating Good Charlotte frontman Joel Madden in December 2006, shortly after he split from pop singer, Hilary Duff.

The couple welcomed daughter, Harlow, now 11, in 2008 and son, Sparrow, now nine, in 2009.

They were engaged in February 2010 and tied the knot in December that year at Nicole's father, Lionel Richie's, Hollywood home.

Speaking to US Weekly about her successful marriage (one that's long by Hollywood standards) in September this year, Richie said: "I don’t know [if there’s] a secret [to it], other than we love to laugh and have fun.

"It’s nice doing the journey of life together. Doing it with somebody else that has the same goals as you is a really fun way to live."

House of Harlow.

In 2008, Richie launched a jewellery line, House of Harlow 1960, named after her eldest daughter. In 2010, she extended the line to include apparel and shoes.

House of Harlow 1960 later became a whole lifestyle brand including eyewear, swimwear, home fragrances, and accessories.

Richie won "Entrepreneur of the Year" at Glamour Women of the Year Awards for the brand. 

TV/writing projects.

After The Simple Life, Richie made her acting debut in Kids in America.

Since then, she's made appearances on HBO’s Camping and Netflix’s Grace and Frankie. Her other acting roles include Empire, Barely Famous, Chuck, and 8 Simple Rules.

Richie recently starred in the NBC comedy series Great News and according to Variety, Richie has just been cast in a regular role in Fox comedy pilot, Richard Lovely.