Error argument to getActive($active->getChildren()) is NULL whereas $active->hasChildren() is true :/

get active pages

<ul class="breadcrumb">
<?php 
function getActive(array $level) {
    $activeInLevel = array_filter($level, function ($page) {
        return $page->isActive(true);
    });
    return $activeInLevel[0];
}?>
<?php $p = $this->pages ?>
<?php $active = getActive($p); echo get_class($active); ?>

<?php while ($active->hasChildren()) : ?>
    <li>
        <a href="<?= $active->getHref() ?>"><?= $active->getLabel() ?></a>
        <span class="divider">/</span>
    <li>
    <?php $active = getActive($active->getChildren()) ?>
<?php endwhile ?>
    <li>
        <?= $active->getLabel() ?>
    </li>
</ul>