Rigidbody inside rigidbody container

Hey there.
New to unity physics and I’m currently trying to get an object with a rigidbody on it to stay inside another pickupable object with its own rigid body container.

Ie, one of these little cat balls, where the bell inside rolls independently of the plastic outer ball.

Ive tried mesh colliders, setting them to convex, sphere colliders, and every variation I can think of.

In every case, the bell inside pings out of the container sphere and rolls away. Can anyone give me a very basic run down of how I would go about this?

Currently, the bell inside is a child object of the outer sphere and both are set to continuous collision detection.

Thanks in advance!

7989879--1026645--zanies+lattice+ball+cat+toy (1).jpg

Hello,

Maybe you could use some kind of hinge joint, or spring joint, or something to connect the rigidbodies to get the visual effect you are looking for, without parenting?

Edit: Have you by the way tried to put the ball in the point in space inside the surrounding outer object, without parenting.