function get_category_count( $parent = 0 ) {
	global $mysqli;
	
	$request1 = $mysqli->query("SELECT COUNT(id) as sayi FROM kategori WHERE parent = '$parent'");
	$row1 = $request1->fetch_assoc();
	$request1->free();
	
	$count = $row1['sayi'];
	
	$request2 = $mysqli->query("SELECT id FROM kategori WHERE parent = '$parent'");
	while ($row2 = $request2->fetch_assoc()) {
		if ($get = get_category_count($row2['id'])) {
			$count += $get;
		}
	}
	$request2->free();

	return $count;
}
// id yazacaksın 1,2,3,4,5
echo get_category_count(1);