Cacher is the code snippet organizer for pro developers

/*
  <div id="parentElement">
      <span id="childElement">foo foo text</span>
  </div>

*/


// Create the new node to insert
var newNode = document.createElement("span");

// Get a reference to the parent node
var parentDiv = document.getElementById("childElement").parentNode;

// Begin test case [ 1 ] : Exist a childElement --> All working correctly
var sp2 = document.getElementById("childElement");
parentDiv.insertBefore(newNode, sp2);