This is a part of a drinking song that I don't know any other verses to. If you've got more verses, post 'em. If you know for sure who actually wrote this song, let me know and I'll put that into the node. I've heared enough conflicting reports as to it's origin that I'll attribute it to that prolific author named Unknown for now.

And Mary McGregor well she was a pretty whore
she'd always greet you with a smile and never lock her door
but on the day she died all the men in town did weep
for Mary McGregor finally got some sleep