arrays - 配列から階層を作成する

Question

私は次のような配列を持っています。

array(
    0 => array(
        'parent' => 'Bigboss',
        'middle' => 'Technicians',
        'child' => 'Players'
    ),
    1 => array(
        'parent' => 'Company',
        'middle' => 'Manager',
        'child' => 'Employees'
    ),
    2 => array(
        'parent' => 'Bigboss',
        'middle' => 'Manager',
        'child' => 'Workers'
    ),
    3 => array(
        'parent' => 'Company',
        'middle' => 'Techinical Lead',
        'child' => 'Employees'
    ),
    4 => array(
        'parent' => 'Bigboss',
        'middle' => 'Workers',
        'child' => 'Employees'
    )
);

この配列を次のように階層的にしたい

parent
=> middle
    => child
parent
=> middle
    => child

以下のように正確に。

array(
    'Biggboss' => array(
        'Technicians' => array(
            0 => 'Players'
        ),
        'Manager' => array(
            0 => 'Workers'
        ),
        'Workers' => array(
            0 => 'Employees'
        )
    ),
    'Company' => array(
        'Manager' => array(
            0 => 'Employees'
        ),
        'Techinical Lead' => array(
            0 => 'Employees'
        )
    )
);

誰かがそれを解決できれば、もっと感謝します。