Iconic '70s Rock Star Behind 3 No. 1 Hits Turns 81

Walter Parazaider is best known for co-founding the legendary rock group Chicago alongside Peter Cetera, Terry Kath, and several other rock icons. The musician turned 81 yesterday, on March 14.

Chicago are best known for hits such as "Hard to Say I'm Sorry", "If You Leave Me Now", and "Look Away". To this day, they remain one of the best-selling rock bands of all time, with over 100 million physical and digital sales to their name.

In 2008, the band was named by Billboard as No. 13...