Thanks very much!
You can't come up with something "at the same time" directly. One definitely influenced the other, even to get the ball rolling.
I'd love to know when it stopped becoming a joke. Was it ever considered to be a joke? They were both disturbed young men, one must have rubbed off on the other. The question is who? People can be so certain that it's Eric on one side and so sure that it's Dylan on the other, but I don't think that's it's as black and white as that. They both were responsible, equally. I just want to know who changed from a loving child, to blood thirsty killer first.
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If Frodo can get the ring to Mordor, you can get out of bed.