I thought that hand gesture was the ok Emoji
which loads of people my age do, my understanding was it was used to say ok, or something looks nice or good. But her fingers do seem to be more spread apart, so maybe you're right.
I've been watching them on and off now and at first i thought they were a strange cult family, then I began thinking the were actually a little more normal than then made out to be, but there is certainly something off about them. I've read loads of forums on them and i'm sure that someone from where they live said that there is something abnormal about them, but i'm not sure how valid that is. They are certainly very religious and they seem to enforce this a lot, but there is only a casual link here with that hand gesture, and i'm sure that if it were the white power gesture they would hide it.
Also they posted a night routine video today and Taina's voice in it irritates me so much, more so that usual. Why is she talking like a child, i had to stop watching. Her vlogs aren't as entertaining anymore anyway.