Katzenjammer Kids has an interesting back story. Turns out the original cartoonist split from W.R. Hearst and drew a competing strip for decades with the other one being called “The Captain and the Kids”. That one ended in 1979, with the Katzenjammer Kids ending n 2006. It was the first to use thought balloons. Due to its 6 decade long run, it is the oldest strip still in syndication at King Features Syndicate.