[rottndog]

I learned that origin from a commercial, of all things. They said it came out of the civil war era. Sounds plausible enough.

[NicknamedBob]

If you're going to craft an urban legend, by all means make it sound plausible.

[blather + dialectal skite, a contemptible person (from Middle English skite, diarrhea, from Old Norse sktr, excrement, from skta, to defecate; see skei- in Indo-European roots).]

And then there's ...
[Middle English shitten, probably from Old English -sciten (as in besciten, covered with excrement), past participle of *sctan, to defecate; see skei- in Indo-European roots.]

[Monkey Face]

WAKE UP!