Lisa performs several songs with Celtic Woman.

Lisa's sister Helen has performed with Celtic Woman in the choir.

Celtic Woman 4 is the fourth release in a compilation series from Valley Entertainment that began in 1998.

Celtic Woman performed the song with lead vocals by Hayley Westenra.

Celtic Woman also recorded the piece.

Celtic Woman is a strange phenomenon.

Celtic Woman has been described as being "Riverdance for the voice."

Celtic Woman has performed three tours in America, with additional performances overseas.

Celtic Woman is scheduled to take "Believe" on tour again from February to June 2013, with the same line-up.

Since then, Celtic Woman have toured the United States and Japan.