Reese Witherspoon and Nicole Kidman Are the Sweetest Friends

When it was announced that Nicole Kidman and Reese Witherspoon were going to co-star in the hit TV show Big Little Lies, we knew they'd make good on-screen friends. What we weren't prepared for was the real life friendship that blossomed between the actresses.

The duo has become the definition of BFF goals, whether they're celebrating milestones together or goofing around on set. So of course, for Kidman's birthday, Witherspoon posted the sweetest Instagram.

"Wishing a big happy birthday to my dear friend, the one and only, mega-talented, #NicoleKidman!!!" she wrote. "I hope you have a gorgeous day filled with laughter and love."

While this message is certainly lovely, this is hardly the first time Witherspoon as sent some Insta-love Kidman's way.

In honor of Kidman's birthday (and the pair's friendship), scroll through some of our absolute favorite Kidman/Witherspoon Instagram moments, and see the cuteness for yourself.

01 of 07

They celebrate National Best Friends Day

Witherspoon gave a shout out to her Big Little Lies co-stars—Kidman included—on the special day. "I'm so grateful for all these wonderful ladies by my side," she wrote on Instagram.

02 of 07

They hang out for "Sunday funday"

Witherspoon and Kidman hung out with fellow co-star Laura Dern to work "on some new lies." Do we sense a Big Little Lies sequel coming? We sure hope so.

03 of 07

They present at award shows together

The friends both presented an award together at the Golden Globes, and they couldn't have looked happier if they tried.

04 of 07

They know how to let loose and be goofy

Filming as much as TV stars do can take a toll on anyone, so it's a good thing that Witherspoon and Kidman know how to have some fun every once and awhile. The stars were beaming in this Instagram as they filmed the final episode of Big Little Lies.

05 of 07

They show each other love just because

Sometimes good friends just can't help but brag about each other. "I love this soulful, creative, brave woman," Witherspoon posted on Instagram. "She is such an inspiration to me! What a dream it is to watch her work in #BigLittleLies."

06 of 07

They encourage each other to shine bright

For Kidman's birthday last year, Witherspoon took to Instagram once again to show her "Aussie gal" some love. "Shine bright today," she wrote next to a bunch of heart eye emojis.

07 of 07

They inspire each other

For International Women's Day, Witherspoon chose to give a shout out to Kidman and her Big Little Lies co-stars, and it was for the best reason. "I feel so lucky to work alongside such talented, strong, fearless, inspirational women! I am so proud of each and every one of these ladies for telling stories about their life experiences and the experiences of other women," she wrote. "It’s so important and can truly change the world. Let's use today to tell the women who inspire us how much they mean to us!"