How to get all child Colliders as single Collider

I have an object with a RigidBody, and it has several children that each has it’s own Renderer, Material, Mesh, and BoxCollider (Yes they are ALL box colliders, nothing else) - How would I go about grabbing all of these colliders as a single collider in a C# script? I’ve tried a few things such as making the entire object a single mesh with a mesh collider, but it doesn’t work the way I need it to.

TL;DR: I have a RgidBody with a Compound Collider. How to get collider as single object in C#?

delete the colliders from the children and add multiple colliders to the parent. would that help?