PHP/MySQL produce multidimensional associative array from database

EDIT

I'm trying to create a little CMS for testing purposes. I've setup a class that creates a navigation with nested elements depending on an array of which the output looks like this:

Array
(
    [0] => Array
        (
            [name] => Home
            [link] => 
        )

    [1] => Array
        (
            [name] => About us
            [link] => about
            [children] => Array
                (
                    [0] => Array
                        (
                            [name] => Team
                            [link] => team
                        )

                    [1] => Array
                        (
                            [name] => History
                            [link] => history
                        )

                )

        )

    [2] => Array
        (
            [name] => Contact
            [link] => contact
        )

)

It works quite good so far but what I finally need is an array with unlimited nesting possibilities. Something like this:

Array
(
    [0] => Array
        (
            [name] => Home
            [link] => 
        )

    [1] => Array
        (
            [name] => About us
            [link] => about
            [children] => Array
                (
                    [0] => Array
                        (
                            [name] => Team
                            [link] => team
                        )

                    [1] => Array
                        (
                            [name] => History
                            [link] => history,
                            [children] => Array
                            (
                                [name] => Pictures
                                [link] => pictures
                            )
                        )

                )

        )

    [2] => Array
        (
            [name] => Contact
            [link] => contact
        )

)

I'm using the following PHP script to populate the array with data from the db:

/**
 * Loops through the children of a page and adds them accordingly to the pages array
 *
 * @param array $parent
 * @param array $children
 */
private function getChildrenPages($parent, $children) {
    $subpages = array();

    foreach ($children as $child) {
        array_push($subpages, array(
            'name' => $child['name'],
            'link' => $child['link']
        ));
    }

    array_push($this->pages, array(
        'name' => $parent['name'],
        'link' => $parent['link'],
        'children' => $subpages
    ));
}

/**
 * @return array Returns an multidimensional associative array with all pages
 */
private function fetchPages() {
    // Prevent multiple db fetches
    if(!count($this->pages)){
        $all_pages = $this->db->get('pages');

        for ($i=0; $i < count($all_pages); $i++) {
            $parent = $all_pages[$i];

            // Get children of current item
            $this->db->where('parent_id', $parent['id']);
            $children = $this->db->get('pages');

            //
            if(count($children)) {
                $this->getChildrenPages($parent, $children);
            }

            if (!$parent['parent_id'] && !count($children)) {
                // Append current item without children to pages array
                array_push($this->pages, array(
                    'name' => $parent['name'],
                    'link' => $parent['link']
                ));
            }
        }
    }
}

This works for 1st and 2nd level items. But how to handle further level items? I guess I'd have to transform my getChildrenPages() function to a recursive function but no clue how to make that in this case. Any suggestions?