Yesterday, I wasn't sure....Today, I am leaning more towards the child being taken by someone they knew and I think they both witnessed, or at least the mother witnessed, who took the child. I think the boys saw it, hence their screaming, and the fact that they haven't been seen since that time.
As I said on another thread here, this would account for the statement, "They took our cell phones so we couldn't call 911". They know who did it, and they know why they did it.
I have no idea if they would have shared that info with LE, though why they wouldn't is beyond me, because, after all, someone took their child. Right now, I am thinking that LE probably does know, or at least have some major clues as to who took her. They're just being very tight lipped until they get the info they need and go through the proper channels and have all their ducks in a row before releasing the information or making an arrest.