I've been thinking on this question for a bit today and I've come to a couple of realizations. First, there's not much that I did as a kid that I feel guilty about because overall, I was a pretty good kid.
Second, though I recall being a pretty good kid, my memory is getting a bit dull in places so I could be wrong about that.
So the "guilty" story goes like this.
When I was about ten, our dog had a litter of puppies. We kept the puppies in the basement as though technically the basement was finished, the floor was tile and it was easier to keep clean.
Prior to the basement being the puppies playground however, it was the teevee room--with my dad's huge rocking chair smack in front of the television. The puppies pretty much were all over the basement and one day I went downstairs and without thinking plopped into my dad's big ole rocking chair and promptly rocked on a puppy, breaking one of it's legs. I recall my parents telling me not to worry about it because it would mend quickly. But very soon after I repeated the same action--and I broke the same puppy's other leg. This time I didn't tell anyone. Plus, I was ready to blame my six-years younger brother if anyone did find out. Now that's pretty bad. And it's also the third thing I realized: I don't feel guilty about any of the times I did something wrong accidentally or otherwise and blamed it on my brother. Because that's what older sibs do. Maybe I'll work harder on mustering up some guilt about it.