Nick Cannon is spending the first week of the new year in the hospital, with wife Mariah Carey by his side.

Carey tweeted that Cannon is suffering from "mild kidney failure." His representative confirmed Cannon's hospitalization. He is in Aspen, Colo., where he and Carey were vacationing.

Carey posted a picture on her website of a miserable-looking Cannon in a hospital bed as she lay beside him. She asked for prayers and said Cannon's situation was "very painful." She later called it a "serious moment that's very tough on all of us."

The pair became the parents of twins -- a boy and a girl -- last year.

Cannon is 31. His representative had no further information Wednesday about his condition, but said he is still hospitalized.