Mariah Carey’s brother has never seen her sober

"She does not have a support system, and she is not mentally capable."

Mariah Carey's brother fears her drinking will kill her and claims he has never seen her sober.

The singer sibling Morgan - who hasn't directly spoken to the singer in two years - fears the star is unable to care for her four-year-old twins Moroccan and Monroe because he believes she is trying to numb her problems with wine and champagne.