There was some sad news Thursday for young children; one of their biggest heroes is stepping away from the limelight.

The Wiggles are the Beatles of the pre-school set.

For 15 years, the Yellow Wiggle, Greg Page, has been the group's heart and soul their lead singer and writer.

On a recent U.S. tour, Page collapsed and missed the next 63 shows and now, he is calling it quits.

Page has been diagnosed with orthostatic intolerance, an incurable genetic condition that causes problems with walking, balance and speech.

"I know Greg loved doing it, but he just can't physically do it anymore," explains Anthony Field, Blue Wiggle. "I was shocked that the Yellow Wiggle was leaving. He's Greg, the Yellow Wiggle."

The Wiggles say they will continue performing with an understudy taking over for Page, but reviews are already mixed.