Sadie would happily admit to herself that she was very concerned and just a tiny bit freaked out. Not that she would let that sway her resolve to help Walter. But it was something she was aware of even as she tried to think of what could be happening to Walter.

She pulls Walter fully into a hug, rubbing his back gently and starts to purr. She stays quiet aside from that, just remains a physical anchor for him until he comes out of whatever the Echo has done.