I'm curious. Exactly how and why did you know it was "naughty"? Where did you get that idea and, if it was "naughty", why did you still need to see the big secret? As for me, my brother and I, when very young, once had a "girl friend" who would take us into our barn and show us her "parts". She had us move away from the openings in the old barn roof so "god" could not see us! This was about as close as I ever got to thinking that what we were doing was wrong/or bad because I was already afraid of "god". I came to think of "it" (sexual stuff) as naughty when our very enraged grandfather ran into the barn and loudly cursed and chased our "girlfriend" away and then gave us a very shaming and disturbing lecture about how bad we all were. It was more about being bad than sex but naughty sex became stuck in my mind and then a lot of other teachings about naughty sex followed that.

In our case, she did not "bribe" us but I believe her intentions were similar to the girl in the OP- she wanted attention but knew there was something wrong with her method. Not sure what the little boy's intentions were but he obviously did not see it as wrong at that moment.

I wouldn't "lose my mind" either but I'd sure take an honest look at my own parenting styles and try to HELP my child deal with life better.

And in our case, the harm came from very inadequate and over reactive parenting which sought to punish and shame us rather than HELP us.