- Dove Cameron as Liv and Maddie Rooney
- Joey Bragg as Joey Rooney
- Tenzing Norgay Trainor as Parker Rooney
- Kali Rocha as Karen Rooney
- Lauren Lindsey Donzis as Ruby
- Emmy Buckner as Linda
- Shelby Wulfert as Heather
- Jessica Marie Garcia as Willow Cruz
- Rena Strober as Becky Bicklehoff
- Emmy Buckner and Shelby Wulfert, Dove Cameron's doubles play Linda and Heather.
- Linda and Heather are named after producers Linda Matthious and Heather MacGillvray, who also co-wrote this episode.
- This is the first time we see Emmy and Shelby's faces on camera and the first time they have actual dialogue throughout the episode.
- This is both Willow and Becky's first appearances in season 4.
- In-universe, Linda and Heather are their actresses' actual names.
- Liv mentions Voltage. She says she ruined two shows - Linda and Heather, and Voltage. Becky also mentions Voltage and Liv's exit.
- Liv auditioned for another show where they were looking for a "Liv Rooney" type, but didn't get the part due to her exit from Voltage.
- Lucas Adams is seen in an "after taping" photo for the episode, although Josh is not in the episode.
- Liv is offered to reprise the role of Stephanie Einstein in Sing It Louder!! after her guest star appearance on Linda and Heather.
- This is one of Dove Cameron's favourite episodes.
- Karen wears the same outfit she wears in her season 4 promotional photo.
| To view the Linda and Heather-A-Rooney gallery, click here.