JQ TREE Nodes not expanding

Question

I created a JQ Tree where I have a nested set of nodes and their children. I have used the below way of populating the nodes in tree.

var allNodes = new Array();
        $.ajax({
            type: "POST",
            url: "@this.FullyQualified("/Metrics/LoadAreaPaths")",
            async: false,
            dataType: "json",
            success: function (resultData) {

                for (var i = 0; i < resultData.TreeViewModels.length; i++) {

                    var node=new Object();
                    node.label=resultData.TreeViewModels[i].Label;
                    node.id = resultData.TreeViewModels[i].Value;


                    if (resultData.TreeViewModels[i].Children.length > 0)
                    {
                        var childNodes = new Array();
                        for (var x = 0; x < resultData.TreeViewModels[i].Children.length; x++) {
                            var nodeChild = new Object();
                            nodeChild.label = resultData.TreeViewModels[i].Children[x].Label;
                            nodeChild.id = resultData.TreeViewModels[i].Children[x].Value;
                            childNodes[x] = nodeChild;
                        }

                        node.Children = childNodes;

                    }

                    allNodes[i] = node;
                }
            }
        });

My problem is it only shows top level nodes and not expanding to show the children upon click. I am not sure what is wrong with this code.

Any help in this regard will really help.