Q: I am wondering if there is any way to link a vertex to follow an animated object? Please help me!
(5/29/98) a

A: Yes, this is possible.
Select the vertex, and while in Sub-Object mode,
apply a Linked X-Form modifier. Use the Pick Control Object
button to select the object to follow. Note that the LX-Form gizmo
will keep the distance to the moving object on the frame you pick it.
So it does matter on which frame you select the control object.