<div style="position:relative; float:left">
    <input type="text" onfocus="renderCalendar(event);" size="50" id="cal" name="cal">
    <div class="wrappercal calwrapper">
        <div class="yearmonth">
            <table class="caltable"><tbody>
            <tr><th width="80%" scope="col" colspan="5">
                <select class="dtcombo year" onchange="changeCalendar()">
                    <option value="2000">2000</option>
                    <option value="2001">2001</option>
                </select>&nbsp;&nbsp;
                <select onchange="changeCalendar()" class="dtcombo month">
                    <option value="1">1</option>
                    <option value="2">2</option>
                 </select></th>
              </tr>
              </tbody>
              </table>
         </div>
     </div>
</div>

function renderCalendar(event){
    var triggerer=event.target.id; // THIS WILL GIVE THE ID OF TEXTBOX THAT TRIGGERED THIS FUNCTION.
  $("#"+triggerer).parent().children(".wrappercal").children(".yearmonth").children(".caltable").children(".year").val(); //not working
}

Parent Div > wrappercal(div) > yearmonth(div) > caltable(table) > year(select)

function renderCalendar(event){
    $(event.target).parent().find(".wrappercal .yearmonth .caltable .year").val();
}

function renderCalendaer(event) {

           $("#"+event.target.id).parent().find(".year").val();

                   }

$("#"+triggerer).parent().find(".year").val() instead.