//create function, it expects 2 values.
function insertAfter(newElement,targetElement) {
//target is what you want it to go after. Look for this elements parent.
var parent = targetElement.parentNode;
//if the parents lastchild is the targetElement...
if(parent.lastchild == targetElement) {
//add the newElement after the target element.
parent.appendChild(newElement);
} else {
// else the target has siblings, insert the new element between the target and it's next sibling.
parent.insertBefore(newElement, targetElement.nextSibling);
}
}