Jennifer Marshall, who played Max’s mom in Stranger Things, is opening up about her character’s absence from the series finale.

The actress, 44, shared posts to Instagram following the series finale on Dec. 31, in which she asked viewers why Max’s mom, Susan Hangrove, did not appear in the Netflix series’ two-hour finale — despite her character’s daughter being in a coma for much of the season.

“Okay folks! It’s over… but where was she,” Marshall asked fans of her character in a video caption on Jan. 1, featuring an image of Max (Sadie Sink) in the hospital. “What kind of mother isn’t there for her child while she’s in the hospital? Give me all your theories…”

Marshall said that her absence from the season was not her choice and that working would have helped her obtain insurance amid her cancer remission. Marshall previously revealed that she was diagnosed with stage three melanoma in 2021.

In a statement to PEOPLE, Marshall said portraying Max’s mom was “the opportunity of a lifetime.” While she didn’t know why the character wasn’t featured in the last episodes, she “would have been ecstatic to return.”

“It would have helped me not only financially, but would have been a mental and emotional uplift after battling cancer for almost two years. Either way, no one is entitled to a role, cancer or not,” she wrote. “My heart remains grateful, and I will always give those involved in the decision-making the benefit of the doubt.”

In another post on Tuesday, Jan. 6, Marshall explained that her own previous cancer diagnosis was not the reason she didn’t film scenes for season 5. “I had cancer, I get it. But I was in remission during the shooting of season five,” she wrote in a caption. “Shooting would have helped me obtain my health insurance through the union.”

She jokingly added, “Maybe they had too many characters, idk but obv Susan Hargrove is THE WORST MOTHER EVER LMAO.”

Marshall appeared in seasons 2 and 4 of Stranger Things, but did not return in the fifth and final season of the series, which saw the students of Hawkins High School (including Susan’s daughter) graduate as many of their parents attended the ceremony. PEOPLE reached out to reps for Stranger Things for comment on the character’s absence.

Marshall has been open about her cancer diagnosis in the past. In a 2022 Facebook post, she detailed her health journey amid the shooting of season 4 of Stranger Things. At the time, “people were so understanding and supportive,” she wrote. Her on-screen daughter Sink, 23, showed her “kindness and compassion” behind the scenes, she wrote, while creators Ross and Matt Duffer also “offered their well wishes and urged me to contact them if I needed anything.”

“Such lovely people I’m thrilled to know and have worked under,” she wrote.

Fans have since called Marshall an “amazing actress” in her comments, while others also wondered where Susan was during the events of season 5. One in particular joked that “Ted ‘Do Nothing’ Wheeler” attended the kids’ graduation, but Susan didn’t. “He’s so funny tho lol,” Marshall wrote of the character, played by Joe Chrest.

Marshall also confirmed that she shot a hospital scene at Max’s bedside, but it “wasn’t a full-fledged scene.”

“It was something we shot during season four,” she clarified.

Stranger Things is available to stream on Netflix.