Second last child without jquery

The text node can be a problem in both lastChild and previousSibling This worked for me:

documentObject.lastElementChild.previousElementSibling

Found the other part of the solution here: https://stackoverflow.com/a/18341945/8486854

You should be able to grab your element with

 documentObject.lastChild.previousSibling

where documentObject is your parent.

Edit

Thank you to David Thomas: Even more accurate would be previousElementSibling because it returns an Element and not a text node:

documentObject.lastChild.previousElementSibling

Sources:
W3Schools
developers.mozilla

If I undestood you correctly you could count from the end with :nth-last-child():

.outer *:nth-last-child(2){
  color: green;
}