Amanda Joy Michalka, often credited as AJ, is an American actress, singer-songwriter, model, and musician who is best known as one-half of the duo Aly & AJ (formerly "78violet") with her older sister, Alyson. She is best known for providing the voice of Stevonnie, the fusion of the titular character and Connie Maheswaran in Cartoon Network's Steven Universe. She later went on to voice Catra in Dreamworks' She-Ra and The Princesses of Power under Netflix.
For Disney, she played Courtney Callum in the 2006 Disney Channel Original Movie, Cow Belles, along with Alyson, who played Taylor Callum. She also played Kate Tweedy in the Walt Disney Pictures film, Secretariat.