I really doubt that this would be a major reason why a household would keep a keris. There are
so many other well know reasons. There have indeed been stories of particular keris (or perhaps just
a particular keris) which had the ability to warn it's owner of danger by rattling in it's sheath. I can't remember the name of that keris off-hand. Perhaps someone else will. Whether or not i believe this seems unimportant to the larger question. The purpose of keris is not to act as a home alarm system.
