Another important tool in the box:  Often it's better to use Point-At than parenting.

With multi-limb attachments like bikes and swings, parenting can get 
tangled or even impossible.   Rotating pedals may roll up the feet 
into twisted messes.  

So consider setting the hand or foot to point-at the pedal.   If the pedal isn't
a body part on its own, parent a little dummy prop to the location where the
foot needs to rest, and set the foot to point-at this little dummy.

With adjustment, point-at can be almost as precise as parenting.

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