Ignore collision of a gameobject that is the child of the same parent?,Ignore collisions from object that is also a child of the same parent?

I am in my opinion still relatively new to coding (this is about year 3) and was wondering if this is possible in an easy way. Now the question might seem confusing so here is it in “code”:

OnTriggerEnter(Collision other) {
    if(other != this.getOtherChildren.GetComponent<Collision>())
        //code
}

The other way that I was thinking was an array with each child in that I loop through. The problem is there are quite a lot and constant collision detection.
And I want to do this as efficiently as possible so I can maybe use the child ignoring code in the future. So I wonder if there is a non heavy way to do this.

Thank you in advance!

,I am not super new to coding (this is about year 3) but I was wondering if this is possible.

The question might seem a big confusing but this is basically what I want to do:

onTriggerEnter(Collision other)
{
    if(other != this.getOtherChildren)
        //code
}

I don’t know if there as easy way to do this? The other way besides at each collision looping through an array, where I put in the other children, and seeing if other is or isn’t one of those. Seeing as I am making a game with a lot of collision checks this would be very heavy and possibly slow the game down.

There is a IgnoreCollision method or you can set up the collision matrix.

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