Everyone has seen the spiral pointed out like below, but a few other familiar images bear close resemblance of significance.
Entire shot for reference.
At Dora's crime scene- which Rust returns to in a later episode and specifically inspects as they pull in tight for a close-up shot.
I think it's pretty clear, Marty's oldest daughter unfortunately crossed paths with whoever this is?
The question is, why was she spared, and allowed to live / not sacrificed? Who is she connected to somehow that spares her death possibly?
Also when we see her take her sister's crown adorned with ribbon and toss it in the tree, is she trying to protect her from being marked as a future target?
In the grainy video they briefly show, the girl in it appears to be also wearing a crown adorned with ribbon...