The NonDocumentTypeChildNode.previousElementSibling read-only property returns the Element immediately prior to the specified one in its parent's children list, or null if the specified element is the first one in the list.
prevNode = elementNodeReference.previousElementSibling;
<div id="div-01">Here is div-01</div>
<div id="div-02">Here is div-02</div>
<li>This is a list item</li>
<li>This is another list item</li>
<div id="div-03">Here is div-03</div>
<script>
  let el = document.getElementById('div-03').previousElementSibling;
  document.write('<p>Siblings of div-03</p><ol>');
  while (el) {
    document.write('<li>' + el.nodeName + '</li>');
    el = el.previousElementSibling;
  }
  document.write('</ol>');
</script>
 This example outputs the following into the page when it loads:
Siblings of div-03 1. LI 2. LI 3. DIV 4. DIV
This property is unsupported prior to IE9, so the following snippet can be used to add support to IE8:
// Source: https://github.com/Alhadis/Snippets/blob/master/js/polyfills/IE8-child-elements.js
if(!("previousElementSibling" in document.documentElement)){
    Object.defineProperty(Element.prototype, "previousElementSibling", {
        get: function(){
            var e = this.previousSibling;
            while(e && 1 !== e.nodeType)
                e = e.previousSibling;
            return e;
        }
    });
} // Source: https://github.com/jserz/js_piece/blob/master/DOM/NonDocumentTypeChildNode/previousElementSibling/previousElementSibling.md
(function (arr) {
  arr.forEach(function (item) {
    if (item.hasOwnProperty('previousElementSibling')) {
      return;
    }
    Object.defineProperty(item, 'previousElementSibling', {
      configurable: true,
      enumerable: true,
      get: function () {
        let el = this;
        while (el = el.previousSibling) {
          if (el.nodeType === 1) {
            return el;
          }
        }
        return null;
      },
      set: undefined
    });
  });
})([Element.prototype, CharacterData.prototype]); | Specification | Status | Comment | 
|---|---|---|
| DOM The definition of 'NonDocumentTypeChildNode.previousElementSibling' in that specification.  |  Living Standard | Splitted the ElementTraversal interface in ChildNode, ParentNode, and NonDocumentTypeChildNode. This method is now defined on the former.The Element and CharacterData interfaces implemented the new interface. |  
| Element Traversal Specification The definition of 'ElementTraversal.previousElementSibling' in that specification.  |  Obsolete | Added its initial definition to the ElementTraversal pure interface and use it on Element. |  
| Desktop | ||||||
|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Internet Explorer | Opera | Safari | |
| Basic support | 4 | Yes | 3.5 | 9 | 10 | 4 | 
| Mobile | |||||||
|---|---|---|---|---|---|---|---|
| Android webview | Chrome for Android | Edge Mobile | Firefox for Android | Opera for Android | iOS Safari | Samsung Internet | |
| Basic support | Yes | Yes | Yes | 4 | 10 | Yes | ? | 
NonDocumentTypeChildNode pure interface.CharacterData, and Element.
    © 2005–2018 Mozilla Developer Network and individual contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
    https://developer.mozilla.org/en-US/docs/Web/API/NonDocumentTypeChildNode/previousElementSibling