The kids of home design reality TV series Fixer Upper are growing up fast.

Joanna Gaines' oldest daughter Ella turns 18 years old on Sunday (Oct. 20), and the night before her birthday, the TV personality shared a peek at all the decorations the family set up for the festivities.

The Gaines planned a fittingly grown-up birthday celebration for their newly-minted adult, including a blue and sage-green color palette and an international flair. Ella's birthday spread includes party plates that read "Oui" and a present that includes a book titled Paris Style.

It wouldn't be a party without some classic birthday decor and treats, of course. The Gaines are celebrating their birthday girl with cupcakes, a banner reading "Happy Birthday" and an array of oversized blue, green and white balloons floating throughout the family's living room.

Watch the video below for a full sneak preview of Ella's birthday party.

"One more sleep til our Ella is 18!" Gaines wrote in her bittersweet post. "My how time flies."

Ella is the second-oldest of the Gaines' five children, and she's the family's oldest daughter.

Chip and Joanna Gaines also share 19-year-old Drake, who recently left home to attend college, as well as 16-year-old Duke, 14-year-old Emmie and six-year-old Crew. Fans have gotten to know the family's four older children, who have been appearing in the background of Fixer Upper since they were toddlers, though Crew was born after the show went off the air.

In 2023, Gaines told People that having children of a wide variety of ages -- from preschool to young adult -- gives her a unique perspective on the parenting experience.

"I think the greatest gift of having a kid go off to college and having a five-year-old toddler is kind of that perspective of, it's not here forever," she reflected at the time. "Don't take it for granted, and cherish these moments. And that's what this five-year-old is teaching me."

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Gallery Credit: Sterling Whitaker