$("#treeview").data("kendoTreeview").expand("li:first");
 $("#treeview").data("kendoTreeview").expand("li:first").children(".k-group");

var counter = 2;

if(counter > 0) {
$("#treeview").data("kendoTreeView").expand('.k-item:first');
$("#treeview").data("kendoTreeView").expand('.k-item:first .k-item:first');
counter = counter - 1;
}

$("#treeview").data("kendoTreeView").expand("li:fist li:first")

var yourTreeSelector = "#youTreeId";
var $tree = $(yourTreeSelector);
var treeView = $tree.data("kendoTreeView");

var $firstItem = $tree.find(' > ul > li.k-item:first');

console.log($firstItem);
//make sure selector is ok and first item exists
if($firstItem.length){
   treeView.expand($firstItem); //expand first item
   var secondSelectedFlag = false; //init flag to false

   //handler method
   selectSecond = function(){
      var $fistChildOfFirstItem = $firstItem.find(' > ul > li.k-item:first');
      console.log($fistChildOfFirstItem);
      //make sure expand will execute only when node exists and was not expanded earlier
      if(!secondSelectedFlag && $fistChildOfFirstItem.length){
          secondSelectedFlag = true;

          treeView.expand($fistChildOfFirstItem);//expand on selected node
          treeView.unbind("dataBound");//unbind method
      }
   }

   treeView.bind("dataBound", selectSecond);//bind a handler method to dataBound event
}

setTimeout(
    function (){
        var $fistChildOfFirstItem = $firstItem.find(' > ul > li.k-item:first');
        console.log($fistChildOfFirstItem);
        treeView.expand($fistChildOfFirstItem);
    },
    3000 //3 seconds is reasonable amount of time
);

$("#treeview").data("kendoTreeView").expand("li:first"); // expands first child
$("#treeview").data("kendoTreeView").expand("li:first li:first"); // expands first child or the first child