Green stuff

I didn't drive my 94 Regal in a couple of days, when I did start driving it around, I noticed that there was some green liquidy stuff underneath my car. But I noticed it to from the neighbor who parked next to me. Her car is a very new Nissan Xterra. Her car has been parked next to mine for a week or so without moving too. Do cars lose this green stuff if you don't drive it alot? Does weather play a part? I live in Chicago, so the weather can flucate any time.

Green stuff sounds like coolant and probably not the Xterra. No, leaks are not normal under any condition get it checked out.