IF Ariahna really did have ODD, then I can see maybe sending her off to someone else while Mom was sick. My ex's daughters half brother had ODD, and he spent a good deal of time at our house. In fact, he had almost the same diagnosis as Ariahna. ADHD, ODD, and some more alphabet soup diagnoses. He was a handful, but to be honest, I don't know what was due to the ODD, and what might have been due to other issues. I am not sure that I could have handled that child while I was sick, mainly because he was the type you couldn't let out of your sight unless you wanted something lost, broken, hidden, or stolen. In that situation, I can understand MAYBE sending Ariahna to a close friend or family member for a couple of days, or having Grandma come in to watch the kids at the house.
But sending all three girls makes 0 sense. However, maybe, and I am trying very hard to be generous with my mindset here, she really did harbor doubts and figured there is safety in numbers. Maybe the mother really is one of those people that does not understand how fast it can happen, or that a molester will go after more than one child, or maybe it never crossed her mind that her kids wouldn't tell her if he did something.
Is there confirmation that the boys really were at the house with her the whole time, or did the boys have somewhere else they could go? I have a brother that will only watch my sons if his wife is at work, because he will not change someone else's little girl.
At this point, yes, I do think that Mom was negligent, because at the end of the day, the buck stops with her. However, what I don't have a set opinion on yet was whether she was negligent because she just didn't know any better or whether she maliciously handed her daughters over to a monster. I would like to know, even though it won't change anything.