May 26 (UPI) -- Billy Joel's wife Alexis is thanking the rock legend's fans for the outpouring of love and support they have sent his way since he announced he is battling a debilitating brain condition.

"We are so grateful for the wonderful care and swift diagnosis we received. Bill is beloved by so many, and to us, he is a father and husband who is at the center of our world. We are hopeful for his recovery," Alexis wrote Monday.

"We look forward to seeing you all in the future," she added.

Alexis is Billy's fourth wife. They have two daughters together -- Remy, 7, and Della, 9.

Billy also has a 29-year-old daughter, Alexa Ray, with his second ex-wife, model Christie Brinkley.