Help! Toddler left in car question

I was recently in Tucson with a friend of mine and we went to check on a
rental property she owns. Her 2 year old was in the car seat, napping, and
my friend left her there when we went to check the house. The windows were
all down (this thanks to me -- my friend thought you could leave the windows
up on a 70 degree day in Tucson! This is the kind of thing that worries me
about my friend.). We were in the house about 15-20 minutes. She never
went to check on the toddler and we could not see the car from the house
unless we were in the front room. We went all over the house and the back
yard. My husband went to check on the toddler during this time. My friend
did not know he did it. I felt VERY uncomfortable about the fact that my
friend left her kid in the car unattended and I mentioned it to her. She
dismissed my concerns, saying that it was a safe neighborhood and one she
was familiar with. She also said that she didn't like to wake up her
daughter from her nap because she was so tired. I do not have children. I
know that I would NEVER leave my baby (if I had one) alone in a car, but
maybe I am just paranoid -- maybe, since I don't have kids, I just don't
understand. What should I do? Should I mention it again, more forcefully
this time? Am I just being paranoid? I would like to hear from some
parents on this. As for the neighborhood -- it's ok. It's not great and
not terrible -- just ok. Lord, I can tell you all that I am concerned about
my friendship with this woman right now because I feel as if I should
mention this again way more forcibly, but I would like some advice first.
Thanks.

--
nimue

"If I had created reality television I would have had a much greater
influence, but then I would have had to KILL MYSELF."
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