The mystery of Keith Olbermann’s sudden cancellation from tonight’s Real Time With Bill Maher is solved, and it proves that the cranky Olbermann does indeed have a heart: His dog is sick.

A spokeswoman for the long-running HBO panel show tells Deadline that Olbermann’s dog “became seriously ill two days ago,” precluding Olbermann from being able to travel to the L.A. taping. Real Time is expected to reschedule the appearance.

Bill Maher Advises Hillary Clinton to Go Away Before U.S. Presidency BidOlbermann was set to be the top-of-show interview guest tonight, but filmmaker Alexandra Pelosi will take the spot in his absence.

The former ESPN host is known for his love of canines — he decried the killing of stray dogs in Sochi prior to the Olympics and two years ago endured the mocking of his Maltese by Craig Ferguson during a visit (sans puppy) to The Late Late Show (“Does it fit in your purse?” Ferguson asked). No word on whether the Maltese is the ill dog, but Olbermann’s devotion was clear: “He does my taxes,” he bragged.

Others set for Real Time tonight are actor Wendell Pierce as the midshow guest, and, on the roundtable, news analyst Linda Chavez, journalist Michael Moynihan and author Salman Rushdie. Real Time With Bill Maher airs at 10 PM ET/7 PT on HBO.