Error in Adding Node to a nonexpanded item

Here is the way that I understand it.  Before a node is expanded it's children do not exist in the DOM.  When you try and inject a node the following code is called.
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updateDOM: function(node, domNode){
    domNode= domNode||node.getDOM('node');
    var previous=node.getPrevious();
    if(previous){
        domNode.injectAfter(previous.getDOM('node'));
    }else{
        if(node.tree.forest && node.parentNode.isRoot()){
            var children=node.tree.wrapper.getElement('.mif-tree-children-root');
        }else{
            var children=node.parentNode.getDOM('children');
        }
        domNode.injectTop(children);
    }
}
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It is trying to get the DOM element of a node that does not exist in the DOM yet. (variable previous).  I'm going to look into this more to make sure that I am not making a mistake in the way I set up my mif-tree.