Jessica Simpson's Three Kids Are Her Mini-Mes as They Celebrate Earth Day in Sunny Photos

Jessica Simpson and her kids enjoyed a weekend outdoors as they celebrated Earth Day.

On Sunday, the 42-year-old singer shared a series of sweet photos with her three kids as they spent time in nature and soaked up the sun to commemorate the annual event that demonstrates support for environmental protection.

The first photo shows Simpson and daughter Maxwell, 10, making silly faces as they stretch their arms out while standing in front of stacks of hay bales. Simpson then snaps a selfie with Maxwell and son Ace, 9, where the musician and her son smile while Maxwell makes a pouty face.

A third shot shows Maxwell, Ace and little sister Birdie Mae, 4, posing on the beach together as Birdie leans into Maxwell for a hug and Ace stands beside the two.

"HEART and EARTH…same letters. Just sayin' 🤍🌎🌍🌏," Simpson captioned the post.

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Last month, Simpson and husband Eric Johnson celebrated daughter Birdie's fourth birthday with a unicorn-themed party.

"Birdie Mae Johnson is 4!!! This adorable wonder of a unicorn kiddo illuminates every color in the rainbow…her favorite color," the proud mom wrote on Instagram alongside photos from the celebration. "Birdie magically makes us laugh AT ALL TIMES capturing attention from EVERYONE!

"She is uniquely and effortlessly herself. This little lady celebrates and twirls through her life in tutus with a pure unique understanding in her soul of glitter sparkles. We love her SO VERY MUCH and she knows it," she continued.

"Birdie is a symphony of STARDUST and born to SHINE. I smiled the entire time writing this because even when she isn't home, I feel her presence glowing inside of me. Bird puts the HAPPY to the BIRTHDAY."

The photos featured the preschooler having a blast with unicorn face paint, dressed in a purple sequined tulle dress and a fuzzy pink coat.

A family photo included in the set shows Simpson's three kids, all looking grown up. Ace made a zany face in the photo while Maxwell sported some seriously impressive makeup.