I guess one can sue for any reason. If the courts can't see that this particular one is frivolous then we're all lost.
Yep, anyone can sue you for any reason. Then no matter how stupid you need to lawyer up and protect yourself. Even if something gets tossed the first day of court you might have a few thousand in legal fees.
I go sued for child support a few years back, by a woman I didn't even know. Her kid was late teens so the "deed" had happened years before. I have a pretty common name and that is what hooked me. Two trips through court, her lawyers asking for extensions. Me just writing out checks to my attorney. It cost me about $1,000 when I was at a time in my life where I was flat broke so it was pain full. Plus my wife was wondering too. I got so pissed about it I called her attorney and asked what it would take to make it all go away and tried to explain they had the wrong guy. Her attorney was some man hating woman so I was pond scum in her mind and just trying to weasel out of paying support. They said they would accept nothing less than a DNA test. I told them to schedule it and they told me I had to pay for it. I told them they were trying to prove that I was the father, they could pay for the tests. They did, I went in for a blood draw and never heard from them again. I actually called her attorney after many months passed and they sent me the DNA tests which, of course backed me up.