As one of the seven members of Chicago as featured on their 1969 debut album Chicago Transit Authority, bassist-singer Peter Cetera's soaring tenor became an integral component of the band's sound on such hits as "25 or 6 to 4," "Feelin' Stronger Every Day," "Just You 'n' Me," and "(I've Been) Searching So Long." When his own composition "If You Leave Me Now" became Chicago's first-ever No. 1 on the Billboard Hot 100 - not to mention in international territories such as Canada, the United