Balloon dynamic string?

Not sure if this has been discussed before, in which case sorry.

In the vid setting up a balloon and string, the direction of the balloon is very rigid. What I’m wondering is how to make it more natural ? I tested a line (subdivided edge) pinned by a vertex with cloth sim and acts great, thing is not sure about the next step attaching one end to a balloon whilst the pinned end is connected to a center object.

I tried parenting the balloon to a vertex on the line, I’ve also tried hooking. The better method seems to be copy location of vertex. However in all cases I can make the balloon follow the line but need the line to follow the balloon.

Btw, the balloon is a rigid body.