Adam Shankman, who has directed several episodes of 'Glee', has tweeted:
Goodbye my amazing and beautiful friend. The lights in my world just grew dimmer. The world just lost one of our best. I love u so much...
I will always cherish you in my heart. Thank you for so many wonderful days. I love you CM ... http://t.co/HW5me8dmLo
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The band's hit singles include You To Me Are Everything, Can You Feel The Force?, and Can't Get By Without You.