It is quite a long article. Click on the link: https://en.wikipedia.org/wiki/Jay_North
Not long ago while surfing through YouTube I spotted a fairly recent interview with Jay North. During the two years "Dennis the Menace" aired he said it was far from a happy time for him. He said he was mercilessly abused and virtually no one gave a damn about him other than using him to make money. That is truly upsetting and it is by far not the first time I've heard about similar abuse of child actors behind the scenes.
Actor Jackie Cooper, who was the child in several movies with Wallace Beery, said Beery was never nice to him off camera. To get him to cry for scenes they would threaten to kill his dog or even cause his dog to cry out in pain - it worked. Cooper wrote an autobiography entitled "Please Don't Shoot My Dog".
It is sad to think of how Jay North was treated. When I was a child, "Dennis the Menace" was one of my favorite TV shows.