Bree (Dorie Barton) is the Actress who portrayed Liv's mother on Sing It Loud! who appears in "Moms-a-Rooney". When Liv discovers that she was not invited to Maddie and Karen's mother–daughter weekend held by Steven's Point's historical society, she calls Bree and the pair joins them. Bree appears to be "too Hollywood" and runs away when she finds Liv's legs covered with leeches, allowing Karen to remove the leeches from her.

Josh Wilcox (Lucas Adams) is a recurring character in the third season. He was Liv Rooney's co-star in Voltage from California, where he played Tess' love interest, Garrison, until "Skyvolt-a-Rooney", when Liv quits the show, allowing Josh to become the new Skyvolt. In "Cowbell-a-Rooney", Liv tries to help Josh become more active and creates a Pilates arena in her backyard. Josh later develops a crush on Maddie after he goes against her in the Cowbell competition, but instead ends up instantly falling in love with her, he almost kisses her in "Secret-Admirer-a-Rooney", and they start dating in "Vive-la-Rooney" They finally go on their first date in "Home Run-a-Rooney", and Josh reveals one of the things he likes about Maddie—her competitive side.

Grandma Janice (Patty Duke) is the twin sister of Hilary, the mother of Karen, the mother-in-law of Pete, and the grandmother of Liv, Maddie, Joey, and Parker. She appeared in "Grandma-a-Rooney" where she has Hillary pose as her as she was running late. In her youth, Janice was a part of the U.S. Olympics Women's Diving Team. Another portion of Janice's life has her working as a globetrotting nature Photographer where she has a lot of photographs of rhinoceroses. When Janice later encountered Joey in Willow's clutches during the viewing of a comet, Janice quoted that what Willow is doing to him is how she had met the man who became his grandfather. The dual role was Actress Patty Duke's final TV appearance before she died in 2016. Grandma Janice's picture is displayed in Aunt Dena's living room.