While Lilith was a recurring character on the show, Marius was only ever mentioned, never seen. His absence was likely due to a combination of factors, including:
* Age: Marius was a young child when Lilith and Frasier divorced, and keeping a young actor on set would have been challenging.
* Storytelling: The show focused on Frasier's life and relationships in Seattle, with Marius living with his mother in Boston. This made his presence in the show less relevant.
* Character Development: Marius's absence allowed for Lilith's character to evolve and be explored without the added complexity of a child.
Despite never appearing, Marius's existence was a constant source of humor and drama on the show. He was often mentioned in conversations about Lilith, and his absence was sometimes used to highlight Frasier's strained relationship with his ex-wife.