Calling a cold sore a "lie bump"

This is very random, but I have a cold sore in my mouth and you know how people say its a lie bump, I know thats a very old saying, but does anyone know where or who started saying a lie bump...I've always wondered where it started...and why...

I remember when I was young and my mom always told me that if you swear your tongue will turn black! This sounds like the same type of thing. The person who made this stuff up usually made it to fool kids into not lying or swearing or this bad stuff will happen to you.