No. 3 did this, physically - she would try to synchronize her breathing with mine. I noticed because she kept staring at me, so I asked. She said it was to help her experience what I was experiencing. I didn't like it because of the staring (that part she stopped at least), nor did I find it helpful, but hey, if she did...

She would also close her eyes sometime to try to think herself into my place during an old trauma - not sure that's mirroring.

When I first brought this stuff up here, unaluna asked a good question: if they're paying so much attention to mirroring you, are they really listening to what you're saying?