Kanye West is "mentally and physically exhausted".
The 39-year-old rapper was admitted to UCLA Medical Centre in Los Angeles earlier this week after suffering from "exhaustion" and "sleep deprivation" and friends of the star a number of factors are to blame.
A source told the New York Post's Page Six column: "Kanye is physically and mentally exhausted. All the pressure became too much for him. He has been working non-stop on the tour, his sneaker and fashion line, plus he is barely sleeping. It has been a particularly tough time for him because of the anniversary of his mother's death, he is still grieving."
Kanye's mother Donda West died on November 10, 2007, from complications following cosmetic surgery.
Kanye, 39, is expected to remain in hospital for a few more days.
An insider explained: "Kanye is still under medical observation. He's doing better, but he still needs to rest. He's expected to stay in the hospital for a few more days."
Meanwhile, it has been revealed that Kanye's three-year-old daughter North and 11-month-old son Saint - who he has with his wife Kim Kardashian West, 36 - don't know he is in hospital and think he is just on a trip.
Speaking about the 'Famous' rapper and his brood, a source told E! News: "North and Saint just think their dad is away now. Kanye wants to get better, so that's a big part in this healing process.
"Kanye is trying to get better, but he has not been released yet because he and the doctors feel he needs more time to recover.
"Kim is by his side now and will stand there till everything gets better."
The mother-of-two - who was robbed at gunpoint in Paris, France, earlier this year - strongly believes the musician will overcome this and vows to do all she can to help her husband because he supported her during her horrific ordeal.
Speaking previously, another source said: "She is just holding things down like Kanye did for her when she needed support.
"Kim is doing much better and is strong. This shall pass she believes."
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