Complex sentence: Ketcham married for a second time to Jo Anne Stevens and moved with her and Dennis to Geneva, Switzerland, where he lived from 1960 to 1977, while still producing "Dennis the Menace".
Split into simpler sentences: Ketcham married for a second time to Jo Anne Stevens and moved to Geneva, Switzerland with Dennis. Where he lived from 1960 to 1977, while still producing "Dennis the Menace".