code: function() {
  			if (!this.children.length)
  				return null;
  				
  			var deepestChild = this;
  			while (deepestChild.children.length) {
  				deepestChild = deepestChild.children[deepestChild.children.length - 1];
  			}
  			
  			return deepestChild;
  		}
docs: Returns latest and deepest child of current tree
  @returns {AbbreviationNode}