make a child of a child from an object to the same object but anther child

make a child of a child from an object to the same object but anther child

Presuming the question is: given that I have an object that has a child object, how can I make a copy of that child object and make the copy a sibling (share the same parent)…

    var newChild : Transform = Instantiate(otherChild.transform);
    newChild.parent = otherChild.parent;
    newChild.localPosition = Vector3(0,0,0); //Your desired position here
    newChild.forward = otherChild.forward;  //Or some other direction here