2.Years before she starred in Girls Trip, Tiffany Haddish played Charlotte, a tour guide who taught Chelsea about carnivorous plants, on That's So Raven.
3.Melissa McCarthy voiced the character of DNAmy, a geneticist obsessed with stuffed animals, on Kim Possible.
4.Sandra Oh voiced news reporter Marsha Mitsubishi in several episodes of The Proud Family before Grey's Anatomy began.
5.Before playing Jerry on Parks and Rec, Jim O'Heir guest starred on The Suite Life of Zack and Cody as Maynard's dad.
6.Star Trek and Heroes star Zachary Quinto played a snooty film director on Lizzie McGuire.
7.Octavia Spencer guest starred as Dr. Evilini, an evil wizard out to steal students' magic, on Wizards of Waverly Place.
8.Solange Knowles voiced Penny's rich cousin Chanel in a few episodes of The Proud Family.
9.If London's dog on The Suite Life of Zack and Cody sounded familiar that's because it was actually Emma Stone.
10.The late great Debbie Reynolds lent her voice to Nana Possible, Kim's kick-ass grandmother.
11.The Shannara Chronicles star Austin Butler went on a horrible blind date with Miley on Hannah Montana.
12.Justin Baldoni starred as an attractive fencing instructor on The Suite Life of Zack and Cody before we started swooning over him on Jane the Virgin.
13.Pretty Little Liars alum Lucy Hale guest starred as Justin's girlfriend Miranda on Wizards of Waverly Place.
14.Before she was running with vampires on The Vampire Diaries, Kat Graham was Jackson's girlfriend on Hannah Montana.
15.Glee star Naya Rivera endured one of Louis's many pranks on Even Stevens.
16.Troy Gentile played Zack and Cody's nerdy friend Jeremy long before he joined The Goldbergs.
17.Cyndi Lauper guest starred as Ms. Petuto, the gang's art teacher that sees potential in Chelsea, on That's So Raven.
18.Rider Strong reunited with Boy Meets World co-star Will Friedle when he voiced Brick Flagg on Kim Possible.
19.Before starring as Tom Garvey on The Leftovers, Chris Zylka played Gabe Lamotti on Hannah Montana.
20.Anthony Anderson was making us laugh as Ray Ray Sr. on The Proud Family long before Black-ish.
21.Before she starred on Friday Night Lights, Aimee Teegarden played Melissa, a girl Jackson takes on a horrible date, on Hannah Montana.
22.Long before Scream Queens, Niecy Nash played the fake television psychic Madame Cassandra on That's So Raven.
23.The Flash and X-Files reboot star Robbie Amell played Max, Casey's boyfriend, on Life With Derek.
24.During her run on Gilmore Girls, Keiko Agena was also voicing Yori, one of Kim and Ron's friends, on Kim Possible.
25.And finally, Selena Gomez guest starred in pretty much everything!
