Actor Sam Neill, best known for his role as Dr. Alan Grant in the "Jurassic Park" franchise, died Monday at the age of 78 from pneumonia, according to his former girlfriend, ABC political journalist Laura Tingle. Neill had been "pretty sick" for the two weeks preceding his death, Tingle revealed to ABC Radio Sydney.

Neill had recently been declared cancer-free after a prolonged battle with stage 3 angioimmunoblastic T-cell lymphoma, a diagnosis he received in 2022. He underwent significant treatment, including chemotherapy and immunotherapy, and later benefited from CAR T-cell therapy, a cutting-edge procedure that reprograms a patient's immune cells to fight cancer. Tests in April confirmed the absence of cancer, a development Neill expressed great excitement about.

However, these treatments left him with a compromised immune system, Tingle explained. "His poor old body just sort of got a bit exhausted," she said, adding that he would have been "annoyed" to fall ill again after overcoming cancer. "He'd had a lot of chemo and a lot of immunotherapy and, thankfully, it finally cleared him of the blood cancer that he had, but that left him pretty compromised in terms of his immune system."

Neill's family announced his passing in a statement on his Instagram page, describing the death as "sudden and unexpected" but noting he was surrounded by family and passed with dignity. They expressed gratitude to the staff at St Vincent's Private Hospital for their care and requested privacy.

Neill, an actor of New Zealand and Australian descent, rose to international fame with his role in the 1993 film "Jurassic Park." He reprised the character of Alan Grant in "Jurassic Park III" (2001) and "Jurassic World Dominion" (2022). His extensive filmography also includes "The Dish," "Peaky Blinders," and "The Tudors," among many other television and film roles. He was also slated to appear in "Godzilla x Kong: Supernova" and "The Last Resort," both scheduled for release in 2027.

Neill was married twice before his relationship with Tingle, first to New Zealand actress Lisa Harrow from 1981 to 1989, and then to Japanese makeup artist Noriko Watanabe from 1989 to 2017. He and Tingle were in a relationship from 2018 to 2021, parting amicably. In his 2023 memoir, "Did I Ever Tell You This?" Neill reflected on his life and expressed gratitude for the women who had been good to him, also noting a sense of loneliness after his divorce and past relationships.