WB 2.11.0

    function add_child_page(page_id)

    {

        //find and select the page in the parent dropdown

        var selectBox = document.add.parent;

console.info(selectBox);

        for (var i = 0; i < selectBox.options.length; i++)

        {

              if (selectBox.options[i].value == page_id)

              {

                    selectBox.selectedIndex = i;

                    break;

              }

        }

        //set focus to add form

        document.add.title.focus();

    }