Luann Stewart (portrayed by Miley Cyrus) is Miley's evil paternal cousin who looks identical to Miley. Her father is Robby Ray's identical twin brother Bobby Ray (portrayed by Billy Ray Cyrus).
Luann has hated Miley since they were small children. Stemming from the fact Miley spent time at her singing lessons instead of with her. Luann is jealous of Miley because she can sing and Luann can't. Once during a talent contest when they were young Luann took Miley's place when she got 'stage fright', or at least that's what she told the adults when in fact she slipped Miley bad catfish so she'd get sick.
In her first and last episode, she visits Miley and Miley doesn't really like her. Luann acts apologetic for what she has done and they reconcile. However before a Halloween party Luann subdues Miley, hogties her with ropes (she went to rodeo camp), gags her with a feather bola and disguises herself as Hannah Montana (Performer) to ruin her career. Miley (who managed to escape her ties and gag), as Hannah, is going as well. Luann's plan was to give a speech and tell everyone that she's Miley so that Miley's secret is revealed. When Luann's about to take off the wig, Oliver turns off the lights and drags Luann offstage. They can't tell Miley and Luann apart, so Oliver says that both of them have to kiss him. Luann's excited but Miley's disgusted so they can tell them apart. As a result, Luann leaves.
Miley's pig pet has the same name as her cousin (Luann).
Luann's only appearance was in the season 1 episode, Torn Between Two Hannahs.