The audacity is breathtaking.. She knocked on a neighbor’s door - obviously they are not friends- and proceeds to lecture him. When did this become a “thing?”
That is precisely why my wife and I refuse to open the door for strangers. They can leave a note, which I will discard unless relevant to my needs. We also have a Ring doorbell and video cameras that we can speak to through our cellphone. Also have a sign that says "Forget the dog, beware of owner." and it displays a gun barrel.
She behaved like a mother-in-law or ex mother-in-law. Maybe she is. He treated her like a stranger but that may be for the little girl's sake.