It's Throwback Thursday and you know what that means ... time for some celebrity Twitter photos.
Katherine Heigl, 34, is the latest star to share a snapshot of her younger self for #TBT, posting:
— Katherine Heigl (@KatieHeigl) September 19, 2013
In the pic, a brunette Heigl is all smiles as she poses on the set of "Wish Upon a Star" at age 17. She looks A LOT different than her days on "Grey's Anatomy."