Complex sentence: Eileen Bellomo (also known as "Snooky"), along with sister Tish Bellomo, sang back-up at early Blondie gigs at CBGB and Max's Kansas City and went on to form another band called the Drop-Outs.
Split into simpler sentences: Eileen Bellomo (also known as "Snooky"), along with sister Tish Bellomo, was a member of the rock group, Blondie. The sisters sang back-up at early Blondie gigs at CBGB and Max's Kansas City and went on to form another band called the Drop-Outs.