Blender 2.79 How to attach rigid body to soft bod

Hello, I am trying to make a necklace with a pendant attached to it. The necklace is just a circular tube. The pendant is just a modified cube with a hole for attaching to the necklace. I need to have this necklace and pendant to move according to my character’s movement. How do I do this?

I am planning to use soft body for the necklace and a rigid body for the pendant.

I am using Blender 2.79 because my computer doesn’t support the newer versions.

Please help. Thank you.