Nicole Richie Reflects on Falling Out with Paris Hilton in Their 20s: 'Not the Best Moments' (Exclusive)

Paris Hilton and Nicole Richie's connection runs deep.

Having known each other since their playground days growing up in Los Angeles, the two socialites turned business moguls have experienced a lot of life together. The starred in the megahit The Simple Life, which premiered in 2003 and ran for five seasons, and they're together again in the new Peacock series, Paris & Nicole, The Encore. But there were moments they drifted apart.

Hilton and Richie, both 43, experienced a rift in their friendship when they were in their 20s and navigated their struggles in the public eye, which included having some of their issues play out on their Fox turned E! reality series.

Looking back on that period in time, Richie tells PEOPLE exclusively, "I think anytime you are separated from your loved ones, it's not the best moments."

Related: Paris Hilton and Nicole Richie's Friendship Timeline: From Childhood Pals to Simple Life Costars

"But Paris and I have more of a sisterhood than I would say, a standard friendship," she continues. "We've been in each other's lives for as long as I can remember since we were 2. So this is just, it's life and it's just been so exciting to be able to shoot this show again. It was great."

Their bond is very meaningful to both of them, as Hilton says, "I just feel so lucky just to have a lifelong friendship like we have — a friendship that's longer than most marriages."

"We've just been through everything together in life since we were little babies," she continues. "I'm just so proud of how much we've grown and just all the experiences that we've been through in life. It made us these really incredibly strong, resilient and amazing women, and I'm really proud of us."

Richie also notes that "when you have a friendship that's gone on this long, you do see each other through all stages of life, and we've seen each other through high school and just every stage of life. Motherhood is yet another stage."

Related: Paris Hilton and Nicole Richie Reflect on Y2K Style Resurgence: ‘It Was the Most Fun Time in Fashion’

In their latest chapter, they teamed for Paris & Nicole: The Encore, which premiered on Dec. 12, and follows the pair as they transform their iconic "Sanasa" song into an operatic affair, which proved to be "so exciting" for them both, Richies shares.

"I knew when I was getting up and getting ready, I didn't know what the day was going to bring, but I was just so excited to be able to get in the car, go shoot with Paris," Richie continues. "I knew that we were going to have a good time, I knew we were going to laugh, and it really made my summer."

Hilton was also excited about coming on board because she knew their original series "brought so much joy and happiness to people around the world for over 20 years now."

"People love the show. It's so timeless. It's brought so much happiness to so many different generations and really stood the test of time and has become the blueprint for so many others," Hilton says. "So that is something that's really cool to celebrate and think of."

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All three episodes of Paris & Nicole: The Encore are now available to stream on Peacock.

Read the original article on People