Simon & Marcy "everyone [working on the series] was pitching in to make this one special". The episode features the voice of Ava Acres, who portrays the young version of Marceline. Acres had previously appeared in the third season episode "Memory of a Memory". As mentioned above, the episode makes notable use of the 1982 song "Where Everybody Knows Your Name" by Gary Portnoy—better known as the theme to the sitcom "Cheers". According to Sugar's father, Rob, on his official YouTube channel, the use of the song started merely as a placeholder. However, as the episode developed, Sugar decided to keep it in
Daniel A. Portnoy for the induction of cell-mediated immunity. Both Drs. Paterson and Portnoy went on to work with biotech companies to develop vaccines for both cancer and infectious disease applications. Numerous clinical trials based on their discoveries have shown promising results as immunotherapeutic treatments for cancer. In 1997, Dr Portnoy moved to UC Berkeley where his lab continues to examine fundamental aspects of "L. monocytogenes" biology, and has expanded to focus on both innate and acquired immunity in the context of Listeria infection. Dr. Portnoy and collaborators have shown that immune cells recognize cyclic di-AMP, a novel and essential bacterial signaling molecule,