I don't mind when my kids come into my bed. In fact I appreciate it more now than ever. I also don't mind if they go to my Ws bed. In fact, I think co-sleeping in a parent's bed is a fine arrangement - no problems with it. In some cultures it is even the norm.
HOWEVER, My beef is that WW is going into the the kids bed. that is what I find odd. it's one thing to fall asleep in your child's bed from time to time. But nightly? I am not so sure.