Kathryn Kates, Actress Who Appeared in 'Seinfeld'and 'The Many Saints of Newark', Dead at 73

Kathryn Kates, a veteran character actress with credits including Orange Is the New Black, Seinfeld and Law & Order: SVU to her name, has died. She was 73.

Kates' representatives confirmed the news to PEOPLE, with Erica Bines of Headline Talent Agency noting that the actress died on Saturday "after a hard fought battle with lung cancer." She added that a memorial for Kates is being planned for the spring.

The performer's manager Bob McGowan wrote in an email, "my heart is broken, she was the best." He added, "The entire time she was sick, she never complained."

A fixture of both the New York and Los Angeles theater scenes, Kates landed highly visible television roles in the mid-'90s, notably appearing as a counterwoman on two of the most memorable episodes of Seinfeld — "The Dinner Party" (or the Babka episode) in 1994 and "The [Marble] Rye" episode two years later in 1996.

Other credits on Kates' screen resume include Matlock, Judging Amy, Lizzie McGuire and Caroline in the City, before she landed recurring roles in hit shows Orange Is the New Black, Law & Order: SVU and the Jennifer Lopez-starring Shades of Blue.

More recently, Kates appeared in last year's short film Welcome to Sarajevo, and portrayed Angie DeCarlo in The Sopranos prequel movie The Many Saints of Newark. She had recently completed acting in a new project, titled Maybe There's a Tree.

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The day after her death, a video was posted to Kates' Instagram account in which she performed a sonnet. Accompanying the clip was a moving caption, which read: "Do not stand at my grave and weep, I am not there. I do not sleep. I am a thousand winds that blow. I am the diamond glints on snow. I am the sunlight on ripened grain. I am the gentle autumn rain."

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"When you awaken in the morning's hush, I am the swift uplifting rush, Of quiet birds in circled flight. I am the soft stars that shine at night. Do not stand at my grave and cry; I am not there. I did not die," the message continued. "Keep me alive in your beautiful hearts with unforgettable memories. Teach others what you've learned from me and I will live in forever. 🤗💐🕊"

Kates' survivors include her sister, Mallory, and brother, Joshua. Deadline was first to report the news of Kates' death.