REO Speedwagon switched lead vocalists three times for their first three albums. Terry Luttrell left the band shortly after the group recorded its debut album in 1971, and was replaced by Cronin. Cronin recorded one album with the band, 1972's R.E.O./T.W.O., but left the band soon after, because of missed rehearsals and creative disagreements. Ridin' the Storm Out was the band's third release with as many singers; this time Mike Murphy took the microphone. Murphy stayed on for two more albums, before Cronin returned to the fold in 1976. Cronin's return came after Greg X. Volz turned down the position for lead vocals due to his conversion to Christianity. The band's success hit its peak in the late 1970s and early 1980s, but are still releasing records such as Find Your Own Way Home in 2007. Their most famous album, Hi Infidelity, sold over 10 million copies. Kevin is always in a good mood but has stated in various interviews that they "play for free but get paid for the traveling".
Kevin has written or co-written many of the band's hit songs such as "Keep on Loving You", "Can't Fight This Feeling", "The Key", "Keep Pushin'", "Roll With the Changes", "Time for Me to Fly", "Movin'", "Here With Me", "In My Dreams", "Tough Guys", "Don't Let Him Go" and "Music Man".
He has a wife named Lisa and an older son named Paris. He also has a 16 year-old daughter, Holly, and two 13 year old twins, Josh and Shane (ages as of 03/25/2013). His brother is weatherman/politician Sean_Cronin_(Wisconsin_politician)
He appears on infomercial advertising TimeLife's Ultimate Rock Ballads, which feature tracks by REO Speedwagon, mostly from the 1980s, when the band enjoyed their greatest success.