In September, Selena Gomez revealed she'd had a kidney transplant courtesy of her best friend, actress Francia Raisa. Obviously, Gomez had kept news of this major operation very quiet but shared in a long Instagram post that she "looked[ed] forward" to sharing the full story with her fans soon. Now, it looks like that time has come.

On Friday morning (October 27), NBC's Today show teased a clip of Gomez and Raisa from an upcoming interview slated to air next week. "My kidneys were just done," Gomez says in the video, wiping at her eye. "That was it."

"I didn't want to ask a single person in my life, and that was the day I came home and found out," Gomez continues before looking over at Raisa, who starred on Secret Life of the American Teenager, "and she volunteered and did it." In her Instagram note, Gomez said Raisa had given her the "ultimate gift and sacrifice" by donating her kidney.

Gomez's operation was necessary because of her lupus, and nearly 60 percent of lupus patients will develop issues with their kidneys, according to this online lupus guide.

The full interview is set to air on Monday (October 30) and Tuesday (October 31) on NBC. Gomez's latest music video for "Wolves" just dropped this week and features a very happy-looking Gomez dancing on a table as she FaceTimes her collaborator, Marshmello. It's good to see her being joyful.