A representative for Usher says the singer's wife, Tameka Foster, is recovering from surgery in Brazil.
Publicist Simone Smalls says Foster "is in stable condition after suffering complications from routine surgery in Brazil. Her husband Usher is with her at the hospital."
No further details were provided. In her statement, Smalls says "the family requests privacy at this difficult time."
Usher was supposed to be one of the performers at music mogul Clive Davis' pre-Grammy party Saturday night, but he had to back out for what Davis called a serious family illness.
The 30-year-old R&B star married Foster in August 2007. They have two young sons, 2-year-old Usher Raymond V and 2-month-old Naviyd Ely Raymond.