Method setSibling

/**
 * Function to set the left or right sibling of a node
 *
 * @param   NodeInterface  $sibling  NodeInterface object for the sibling
 * @param   boolean        $right    If set to false, the sibling is the left one
 *
 * @return  void
 *
 * @since   4.0.0
 */
public function setSibling(NodeInterface $sibling, $right = true)
{
    if ($right) {
        $this->_rightSibling = $sibling;
    } else {
        $this->_leftSibling = $sibling;
    }
}