I have a leak it’s green only leaks overnight back by the driver side near back tires

What is your question?

The leak only happens overnight while it’s park. It’s green like anti freeze which surprised me because if it’s the radiator why would the leak be in the rear of the car? Other wise car runs good. I bought off a 94 year old lady who has only 23,455 miles on it.

What makes this problem better or worse?

When it’s parked overnight

How long has your 2009 Chevrolet Cobalt had this problem?

Couple days