I see no problem with the scenario the OP observed. As long as the mom turned off and locked the car and had the keys with her the baby was in no danger. I would not leave any baby/child in a running car! I would not leave a baby in a locked car and run into Wal-Mart, but a small place where I could park right out front and see the car I would have no problem with. It's tough when you are a first time mom! I laugh now at some of the crazy things I worried about! I remember being afraid DD would pull her little sock off and put it in her mouth and suffocate when she was less than a month old Try to follow things out to their logical conclusion and it should alleviate your fears. When people say things like "anything could happen" actually sit down and think about what could really logically happen, and usually you will find the answer is nothing much!