Multiple colliders, One Hitbox

So I’m currently working on a VR Game.
In order to be able to grab an object, I need to access his collider(s).
If they’re directly on it, no problem, it add them and all but if those are on his children → problem problem!
It’s doesn’t even recon them, even with a GetComponent(s)InChildren…
When I do that it just shifts indefinitely the collider to one of the colliders of the children → Doesn’t work at all…
So i kind of need to squeeze an array into a single variable I guess? But I really don’t know how…
Can someone help me please?

Thank you very much

Up!
Could someone help me please? Thanks guys!

Okay so What i’m trying to do is to copy and paste the colliders from my children to my parent.
So i’m doing smthg like that :

                Collider[] coll = this.GetComponentsInChildren<Collider>();
                foreach (Collider colli in coll)
                {
                    Collider jack = colli;
                    GameObject.AddComponent<Collider>(jack); ///But that don't wanna work any way I try to turn it!
                }