Neighbor's 3-year old is seemingly home alone. What would you do?

It's been 24 hours and I just can't get this series of events out of my head. It left me feeling...disturbed. Bothered. Concerned.

Yesterday morning around 8:30, just as I was pulling Jonas out of his car seat to go back into the car, I saw a little girl running on the other side of the street in her nightgown, barefoot, running in the direction of a major 50 mph crossroad. I thought it was odd so when I saw that she was looking at me, I waved.

She looked like she had been crying and yelled to me from the opposite sidewalk that her mommy, daddy and grandpa were not home, then tried to cross the street. Of course, I ran to her and checked that cars were not approaching. I immediately recognized her as a little girl in Gabriel's class, guessing she must be around 3-4 years old.

I called Adrian to let him know what was going on, since he was inside getting ready and I figured that he would wonder what I was up to if he saw my car at the house but not me. The only thing I could think to do was leave a note and bring her back to my house, because let me tell you. If I walked into my house and some stranger was hanging out with my kids, I'm pretty sure I would lose my ish.

We walked in and I yelled out several times, but nothing. The whole situation was just bizarre. The little girl wanted to put clothes on and started stripping down. Mommy instinct kicked in so I helped her but at the back of my mind, I couldn't help but wonder what her parents would think if they walked in.

Luckily, a few minutes later the neighbor drove up and I ran out to question him about the parents. He was able to give me a phone number for the grandpa who lived across the street and when he came out to meet and speak with me, I was shocked to find out that the little girl's mother was upstairs asleep. I could tell by his tone and attitude that he was disgusted by the whole situation. He took her back to the house and the mother called me about 20 minutes later to apologize and thank me.

At the end of the day, the little girl is okay and maybe I'm making a mountain out of a molehill. She was taken care of and everything worked out fine, but I just can't help but think of the "could-have-beens"... What if the person who found her had been some dirty perverted slimeball and not me? Or the drug cartel wanting to use her as a mule (we live 10 minutes from Mexico, it happens, as awful as it sounds)? Or what if she had made it to that road and was hit by a car?

So now the question begs, do I do anything about this? I honestly hadn't considered anything until after I spoke with my mom, who immediately asked if I was going to report the situation to CPS. My husband, on the other hand, sidles more on the edge of not getting involved in other peoples' business. I was thinking that maybe I would invite her over for a play date and try to get to know the family.

I feel for the mother - being a mom is exhausting and there are a million possible explanations for why she overslept like she did. Everybody makes mistakes; hell, parenting is all about trial and error. However, I can't imagine what I would feel if something happened to that sweet little girl, knowing that I had a weird feeling about the whole situation and didn't do anything.

So I ask, would you do anything? 

Or do you feel like my husband, that it doesn't concern our family?