A while back a 13 year old child having surgery at Children's Hospital in Oakland, CA suffered complications that led to her death. Unfortunately there is no longer any activity in the brain, this is brain death and is irreversible. Clinical death is declared based on external observations such as no pulse or respiration, it often occurs that people recover from being declared clinically dead.
Jahi's parents suffer from severe religious delusions, so bad that it is wrecking their lives now as they keep their dead child's body hooked up to machines and expect prayer will lead Jesus to give the child a kickstart. It ain't gonna happen, it could not possibly happen, but because of their severe religious delusions they are not able to differentiate between objective reality and the Jesus fairyland in their heads.
I share their grief, and I have very sincere sympathy for this poor family, but they need to learn that reality trumps religion whenever there is any conflict at all.
Nothing fails like prayer.