Conversation so far:
What were Chicago's last albums?
Chicago: Greatest Hits Live and Chicago XXXVII: Chicago Christmas are the band Chicago's last albums.
Are there any other interesting aspects about the Chicago band article?
After auditioning over 30 potential replacements for Terry Kath, Chicago decided upon guitarist and singer-songwriter Donnie Dacus.

Question: Why did they need a replacement?
Self-contained rewrite: Why did Chicago need a replacement for Terry Kath?