In a preview clip posted Friday for the interview, which airs Monday, Gomez describes the kidney transplant as a "life-or-death" move.
“My kidneys were just done," she said. "That was it and I didn't want to ask a single person in my life. And she volunteered and did it."
Gomez received the transplant as part of her ongoing fight against lupus, an autoimmune disease that often attacks the kidneys. The 25-year-old singer has publicly battled lupus for the past two years, sharing that she also underwent chemo as part of her treatment.
In September, Gomez revealed her transplant via Instagram, explaining, "it was what I needed to do for my overall health."
She shared a picture of her and Raísa in side-by-side hospital beds, revealing that her "beautiful friend" was also her donor.
"She gave me the ultimate gift and sacrifice by donating her kidney to me," Gomez wrote in the caption. "I am incredibly blessed."
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