This letter is so revealing into the bizarre psychology of the Wilson family at the time... despite that Dennis was a 23-year old rich, famous (though at the time of dwindling fame), and independent adult/rock star, he still had to write a promissory type note to his dad for borrowing the camera. I’ll bet this was written at Murry’s insistence to Dennis (the Menace).
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Totally something that might be expected at age 13, but just a bit unthinkable and seemingly a bit demeaning of someone who’s an adult, let alone a famous adult celebrity. Obviously to Murry, Dennis was still just Dennis the screwup kid, and that is probably all he’d ever be
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This. It's just... Weird.
And I guess Dennis could have bought his dad a new camera in the blink of an eye.