> Quote - I wonder if the the bone can have any effect to the group of its siblings?

Yes, a joint parameter channel can react to rotation and scaling in a sibling actor. It is the "otherActor" line that tells the JP channel which actor to respond to, and the presence or absence of a "flipped" line in the channel determins the sense of the reaction. I can't really give you much detail about this, because I don't know a lot about it.

In the cr2 attached above, the lThigh will respond to scaling and rotation of the rThigh, but the rThigh will not respond to these in the lThigh. The diffrence is that the joint channels in the lThigh point to "otherActor rThigh".