When it came to choosing a dress for her 2024 high school graduation, Brooke Shields’ daughter, Grier Henchy, 18, went no farther than her mother’s closet.

“Her graduation dress was my first wedding dress,” Shields recalls of the garment she donned to marry tennis legend Andre Agassi in 1997.

“We had to rebone it a little bit so it was tight and sleek,” says Grier, 18, who has just started her freshman year in college. (She enrolled at Wake Forest University alongside her older sister Rowan, who is 21.)

“We took out all the poof because I didn’t want it poofy.” Shields adds: “And we made it strapless.”

“She looked great in it,” adds the 59-year-old celebrity. “It’s an honor when people want to wear your clothes. Normally, they do not think I am cool.”

In this week’s PEOPLE, Shields and her two children, Rowan and Grier (whose father is Shields’ second husband, Chris Henchy), reveal what home life is truly like, including plundering their mother’s unique closet.

Shields, who is now a first-time empty nester, says nothing is off limits. “Honestly, they can wear anything just to have it have another life—you save the stuff and wonder why,” Shields says. “Is it similar to a large-scale Sotheby’s auction?” I sincerely doubt it. Unless they are iconic objects. So having another life feels fantastic.”

The outfit she wore to marry Agassi (whom she divorced in 1999) is an excellent example. “He’s a good guy, so to me it was really like a big full circle moment,” she explained, “and it honors something, and I think that’s healthy.”

It’s not the first time her girls have donned one of her iconic dresses. Rowan elected to attend her high school prom in 2021 wearing her mother’s flaming red Richard Tyler-designed dress. Brooke had previously worn the dress at the 1998 Golden Globes.