Sharon and Aimee Osbourne had to cancel their stage debut in a London production of "The Vagina Monologues," due to the daughter's unidentified illness.

The pair was set to perform Tuesday in London's West End but Aimee was too sick, "E!Online" reported.

The famous British family flew to Los Angeles so Aimee could be treated in California.

"They were both very much looking forward to appearing in the show, but Sharon's focus now has to be on the family and, more importantly, Aimee's health," read a statement from their publicist.

"They apologize profusely for letting the cast down and wish them all the very best for the upcoming production. They hope everyone understands and would be very grateful for privacy at this sensitive and difficult time for them."

No other details were disclosed about the condition of Aimee, who is the daughter of rocker Ozzy Osbourne.