Hi Tim Parent a prop to the desired area of  the "grabee's" body ***(prop later to be made invisible)***

Turn on IK of the "Grabbers" hand and change the hand's parent to the prop.

move/animate  the "grabee"
and the "grabber's" hand should Follow.

Not the  most elegant solution and you still may have to fix the hand position in the graph editor depending on how much movement is involved,
but  thats all I can Come up with barring some amazing python script to do it.

Cheers

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