"It is an honor to know and walk through this world with you," wrote Reese Witherspoon

Reese Witherspoon shared a sweet birthday shout-out to friend Oprah Winfrey this week.

On Wednesday, as Winfrey turned 66, Witherspoon paid tribute to her A Wrinkle in Time costar by sharing a photo of the two smiling together on Twitter, writing with it a heartfelt message to the entertainment icon.

“Happy birthday @Oprah!! ?,” Witherspoon, 43, tweeted. “It is an honor to know and walk through this world with you. Thank you for sharing your wisdom and advice… it is truly invaluable! ??”

During their time making the 2018 Disney film — which also co-starred Mindy Kaling —Witherspoon got to know Winfrey beyond her larger-than-life television persona.

“She really is like your best friend,” Witherspoon told WSJ. Magazine in 2018. “She’s relatable, she loves to have a good time, she loves to drink a margarita.”

“We had at least four hours doing hair and makeup every day, and Oprah could have had her own trailer,” Witherspoon added of her bonding time with Winfrey. “But she decided she wanted to do it with Mindy and myself.”

The instant feeling of friendship was mutual for Winfrey, who told the magazine at the time that she had a blast working with her costars.

“I can’t remember the last time I had that much fun,” said Winfrey. “We were fired up. We were alive in that trailer every morning. Reese was the DJ, playing all this old Southern blues music. We listened to more Sam Cooke than I’ve heard since I was a kid.”

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From left: Mindy Kaling, Reese Witherspoon, Oprah Winfrey and Storm Reid, 2017
| Credit: Alberto E. Rodriguez/Getty Images

The pair first met on The Oprah Winfrey Show when Witherspoon was promoting her 2005 film Walk the Line, which went on to win the star an Oscar.

Witherspoon and Winfrey both share country roots — as a teen, the former talk show host moved to Nashville, where the Big Little Lies actress grew up.

“I think Southern girls have a thing,” Winfrey told WSJ.

Wrinkle in Time director Ava DuVernay also wished “Queen” Winfrey a happy birthday, sharing a video on Twitter of the mogul dancing to “The Cupid Shuffle.”

“Queen. She shows me how to live life with intention and integrity. To be brave in my dreaming,” wrote DuVernay, 47, who also worked with Winfrey for her 2014 film Selma. “To listen to the voice inside waiting patiently to be heard. To hold the hand of each day, like the friend that it is. Happy Birthday, @Oprah. And thank you!”