Jessica Biel reunites with former '7th Heaven' costar Beverley Mitchell

The duo played sisters Mary and Lucy Camden on "7th Heaven."

Jessica Biel and her "7th Heaven" costar Beverley Mitchell had a sweet reunion while supporting a good cause over the weekend.

The former co-stars of the popular TV series in the '90s attended the Global Down Syndrome Foundation's 16th Annual Be Beautiful to Be Yourself Fashion Show at the Sheraton Downtown Denver Hotel in Denver, Colorado, on Saturday.

The pair posed alongside each other on the red carpet and donning big smiles for the camera.

Biel and Mitchell played sisters Mary Camden and Lucy Camden, respectively, on "7th Heaven," which was created by Brenda Hampton and ran for 11 seasons between 1996 and 2007 on The WB and later on The CW.

The beloved family drama followed the Camden brood, including its patriarch, Rev. Eric Camden (Stephen Collins), and matriarch, Annie Camden (Catherine Hicks), as well as their seven children, as they navigated the ups and downs of life.

Biel has remained close to Mitchell since the show ended.

"Jessie and I see each other often, cause obviously, like, she's my bestie, she's my ride or die," Mitchell told "Entertainment Tonight" about her decades-long friendship with Biel in an interview last June.

Biel and fellow "7th Heaven" castmate Mackenzie Rosman served as bridesmaids at Mitchell's 2008 wedding to husband Michael Cameron.

Biel also attended the event on Saturday with her two sons Silas, 9, and Phineas, 4 whom she shares with husband Justin Timberlake as well as her niece Zaya who was honored during the evening as GLOBAL's Ambassador.

In photos shared on her Instagram Sunday, Biel is seen walking the runway at the event with Silas, Phineas and Zaya.

"Last night was truly special at the #BeBeautifulBeYourself fashion show," she wrote in the caption. "Walking the runway with my amazing niece @lovelyzayab was an unforgettable honor. Huge thanks to the @globaldownsyndrome foundation for creating such a profound, empowering event and for all the incredible work you do. My heart is so full. ♥️."