A couple of years had passed since 12-year-old Audrey Vaughan had set foot in the playhouse built especially for her when she was just two. Did she really have to spell it out to her parents? The plastic kitchen set was clearly for babies. And she was far too big for the little blue plastic chairs. Quite simply, she was growing up and her playhouse wasn’t.

With the finishing touches just put on this week, the San Jose 7th-grader turned her little girl playhouse built in her backyard by Denver-based La Petite Maison in 1998 into a tween club house. And while her parents, Belinda and Matt Vaughan, and her grandmother and aunt helped out, this girl loves HGTV. And she knew “Hidden Potential” when she saw it — even in a room no bigger than six-by-eight feet. At the same time, her 1st-grade brother got in on the act, and the family turned what had been a storage shed attached to the rear of the playhouse into a tongue-and-groove pine-paneled “fort” with a loft just for him.

Audrey started as all good designers do — with a fabulous fabric for inspiration. Needing just a couple of feet to cover the top of an antique chest, the velvety fabric in green and blue florals set the tone.

She painted the walls and ceiling a pale green, and the old blue and white vinyl flooring was covered with peel-and-stick parquet squares. A fresh sheet of blue contact paper lined the back of a shallow, antique bookcase — just deep enough for Audrey’s collection of Nancy Drew mysteries.

A white shelf was painted pink and became the ideal spot for her favorite polka dot teacup from her grandmother, a pink stuffed bear she earned for selling Girl Scout cookies, and a framed photo of herself and her mom. She added a blue shag rug from Lowe’s and hung a dream catcher in the window.

But design is a collaboration, and creative clashes are inevitable. When the plastic chairs went out, it was uncertain whether a pair of green canvas directors’ chairs from Pier One should come in.

“You said we shouldn’t get them,” Audrey said to her mom.

“I know,” Belinda answered.

“But I wanted them,” Audrey said.

“I know,” her mother said.

And, well, sometimes 12-year-olds are right.

On her birthday, five girlfriends crammed into the “tween” hangout.

“They liked it a lot,” Audrey said. “I’ve been waiting forever to change it.”