Sounds like a good young woman, though I wonder about the 2:30 am video games with an 8-year old and why the door was open according to the neighbor who called. Maybe a sleepover with the nephew? I'd still be scared to leave the door open at that hour, though, especially with a child around. Also, 5 officers seem a lot for a welfare check, so maybe there was more going on than we know.
Poor neighbor - he was just trying to help.
I would have done the same. Poor nephew, who had to see this, and poor, poor sister who is just heartbroken