Now her family is demanding answers.
Jahi McMath, 13, and her mother Nailah Winkfield first arrived at Oakland Children's Hospital on Monday.
McMath was apprehensive, but her mother says she convinced her daughter things would be fine.
"She smiled when she walked in this hospital and I told her this surgery is to make you better," Winkfield said.
McMath went in to have her tonsils removed because doctors said it was to help with her sleep apnea.
But in recovery, the 13-year-old girl had disturbing complications.
"My daughter had actual clots sliding out of her mouth and they gave me a cup and said, 'here catch them with the cup so we can measure them,'" Winkfield said.
McMath's grandmother Sandra Chatman is a nurse at Kaiser Permanente Medical Center in Oakland and said she was surprised by what she calls a lack of attention by Oakland Children's Hospital staff.
"I went in and I said 'is this normal, do you guys find this to be normal?' And they said 'I don't really know,' and I said 'well then get a doctor,'" Chatman said.
McMath took a turn for the worst on the last day.
"My daughter went into cardiac arrest and died and they brought her back and now she's brain dead," Winkfield said.
They are shocked. What's worse is they say hospital staff is asking to consider removing McMath from life support.
"They just have a social worker follow me around all day long asking me 'do you have any other family that needs to see her?' like trying to put a rush on it," Winkfield said.
The family is now demanding for Oakland Children's Hospital to conduct an investigation to find out how McMath could have died following a seemingly routine surgery.
An Oakland Children's Hospital representative was not available for an interview, but spokesperson Melinda Kriegel released this statement: "We're very sad about this outcome, about what's happened to her, but at this point I have no information on the details of the surgery. We will certainly investigate what happened. In any surgery there are risks and there can be unexpected, unanticipated complications."
The family says they do not want to remove McMath from life support.