Someone

$sub_sections: Array
(
    [0] => Array
        (
            [id] => 8
            [name] => Pressure Vessels
            [parent_id] => 3
        )

    [1] => Array
        (
            [id] => 9
            [name] => Boilers
            [parent_id] => 3
        )

    [2] => Array
        (
            [id] => 10
            [name] => Lifting Equipment
            [parent_id] => 3
        )

)

need to array_search this array's parent_id field
$search_value is 3
return true if its found in the array at all or false if not