I understand your confusion, but that's the formatting - quoted parent is below the child post - then that post's replies follow in the discussion view. The top post is always quoting its parent below it, the different bg makes it distinct. Just need to get used to it, same on X.

There really is no other way to include the parent otherwise, you have to break the hierarchy at some point, the other form would need to omit the parent body and show a 'parent' link but we want to include its body.