Show the number of guests on invoice_customer_pdf.php

<?php foreach ($displayData['reservation']->reserved_room_details as $room) : ?>
	<p>
					<?php echo JText::_("SR_ADULT_NUMBER") . ': ' . $room->adults_number ?>
				</p>

                <?php if ($room->children_number > 0) : ?>
				<p>
					<?php echo JText::_("SR_CHILDREN_NUMBER") . ': ' . $room->children_number ?>
				</p>
				<?php foreach ($room->other_info as $info) : ?>
					<ul>
						<?php if (substr($info->key, 0, 5) == 'child') : ?>
							<li>
								<?php echo JText::_('SR_' . $info->key) . ': ' . JText::plural('SR_CHILD_AGE_SELECTION', $info->value) ?>
							</li>
						<?php endif; ?>
					</ul>
				<?php endforeach; ?>
                <?php endif; ?>
	<?php endforeach; ?>

$database = &JFactory::getDBO();
$database->setQuery("SELECT children_number FROM #__sr_reservation_room_xref 
  WHERE reservation_id = '" . $reservationId . "'");
echo $database->loadResult();

$reservationId = $displayData['reservation']->id;