I'm glad your family is safe. That's what it's all about. You didn't say if you did or not, but I'll assume that you drew down on them? If someone came up and stuck a knife in my face, the least of what they would get is the business end of my .45 staring them down. Displaying a deadly weapon such as a knife in a threatening manner is a good way to get shot, real quick. Like you said, they're lucky the police came to pick them up instead of the coroner.