The show may be 'So Yesterday' now, but the 28-year old actress was feeling nostalgic on its 15th anniversary.
Hilary Duff is paying tribute to the quirky tween role that made her a household name.
It's hard to believe, but it's been 15 years since Lizzie McGuire -- the TV show that kicked off her career -- aired its first episode. The 28-year-old actress took to Instagram on Wednesday to celebrate with a video featuring snapshots of her and her co-stars from the popular Disney Channel series.
PHOTOS: Hilary Duff Recreates Iconic 'Lizzie McGuire' Moments
"Happy 15 year anniversary #lizziemcguire," she captioned the Flipagram video, which features the Golden Girls theme song in the background. "Thank you to everyone who helped [make] this show great! I know we were grateful to be a part of your lives and hope we made you smile and feel like you had a friend in us."
Nostalgic fans were quick to comment, writing things like, "This is literally what dreams are made of," "OMG my heart!" and "Catching feels for the crimped hair and butterfly clips."
NEWS: Hilary Duff Gets Candid About 'Torturous' Lizzie McGuire Years
Many also gushed over the ultimate BFF trio -- Lizzie, Miranda and Gordo -- we grew to love.
And let's not forget about mean girl Kate, always trying to bring Lizzie down.
Or that time Lizzie kissed her celeb crush Aaron Carter.
WATCH: Is This the Hottest Hilary Duff Has Ever Looked?
Fifteen years later, Duff is all grown up!
Earlier this week, she flaunted her curves in a white pantsuit.
"Casual Pimp suit this morning for @todayshow," she wrote on Instagram.
She also recently flashed her cleavage in a sexy two-piece, while vacationing with one of her friends.
Not only does she have a killer bod, but she's also the mother of 3-year-old Luca Cruz Comrie, whom she shares with her ex-husband, retired Canadian hockey pro Mike Comrie. The two were married in 2010, but announced their divorce in 2015, citing irreconcilable differences.
WATCH: Hilary Duff Reunites With 'Lizzie McGuire' Co-Stars
Last April, Duff -- who currently stars on TV Land's Younger -- reunited with her on-screen BFFs Lalaine and Adam Lamberg, and brother, Jake Thomas, and the Internet couldn't contain their excitement.
Watch the video below to hear more.