<P> In the episode "Linda and Heather - a-Rooney", the effects of Liv leaving Voltage to be with Maddie caused her to have a hard time finding another role . She does get a guest role on "Linda and Heather" which she nearly causes to stop production until she and Parker come up with a plan to keep it from ending . By the end of the episode, Liv is told that they want her to reprise her character for the sequel to Sing It Loud! called Sing It Louder!! </P> <P> The back of Emmy Buckner's head is used to help create the character of Liv . She is Dove Cameron's look - alike double . </P> <P> Madison "Maddie" Rooney (Dove Cameron) is Liv's identical twin sister and the second eldest child of the Rooney family . Like Liv, she is older sister to Joey and Parker, as well as a sophomore at Ridgewood High . She is captain of the girls' basketball team of Ridgewood High and is equally diligent to her team captain duties as her studies . Her main love interest is Diggie, captain of Ridgewood High's boys' basketball team . But because of his constant moving, they break up . Her new love interest is Liv's co-star in Voltage, Josh . Her catchphrase is "Bam! What?!", a phrase she came up with once at age 11 when she was telling Karen that she beat the boys at basketball . She is sometimes called Mads by Diggie and Willow, such as in "Slump - a-Rooney" and "Shoe - a-Rooney". In "Sleep - a-Rooney", it was revealed that Maddie's full first name is "Madison". It is shown that Maddie shares the personality quirks of her father, Pete, as seen in "Dump - a-Rooney", when the pair shows their competitive side while preparing for a two - on - two basketball tournament . In "Shoe - a-Rooney", Maddie becomes addicted to a comfortable pair of high heel shoes that she borrowed from Liv . When the addiction becomes problematic, Liv, Willow, Diggie, and Stains stage an intervention which ends with Liv dropping the shoes into a woodchipper . </P> <P> In "Space - Werewolf - a-Rooney", Maddie injures her leg and is unable to play basketball . In "Pottery - a-Rooney", Maddie tries taking up the new hobby of pottery; however, it does not work out and she ends up going back to basketball . In "Helgaween - a-Rooney", Karen uses hypnotherapy to try to get Maddie over her fear of using her injured knee to shoot a three - pointer, but Maddie instead has a nightmare that she and Liv have a triplet named Helga . Maddie temporarily becomes the new sensei for Parker's karate class in "Match - a-Rooney". In "Muffler - a-Rooney", Maddie recovers from her knee injury and successfully plays basketball again . </P>

Who acts as maddie in liv and maddie