Maybe you recognize him from your childhood Disney Channel shows Sonny with a Chance, So Random, or the iconic Zac Efron movie 17 Again. Sterling Knight had a short guest appearance as Kip, one of the boys who dared their friend to lie in wet cement on Grey's Anatomy Season 4 Episode 16.
Sarah Chalke isn't new to medical TV shows as you may know her as Elliot Reid from Scrubs, or even as Stella Zinman, a dermatologist on How I Met Your Mother. On Grey's Anatomy Season 9 Episode 19 Casey Hedges comes into the hospital with her son who ends up having a rare Kawasaki disease.
Sarah Paulson, from American Horror Story, makes a quick guest appearance as a younger Ellis Grey, Meredith's mother on Grey's Anatomy Season 6 Episode 15.
We finally met the other Shepherd sister and surprise surprise, hello Amy Acker, here to complete the family tree of goddesslike genes on Grey's Anatomy Season 15 Episode 21. Amy Acker is well known for her portrayal of Root on Person of Interest.
Abigail Breslin, one of the most recognizable child actors, portrays Megan Clover, a girl who lacks the ability to feel pain on Grey's Anatomy Season 3 Episode 3. She's most known for her acting in some classic movies, Definitely Maybe, My Sister's Keeper, and Little Miss Sunshine.
One of the most surprising finds! Rachel Brosnahan the protagonist of Amazon Prime's The Marvelous Mrs. Maisel made an appearance on Grey's Anatomy Season 9 Episode 14 as Brian Weston, a trans boy who requests top surgery to remove his breasts.
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