public function AllChildrenIncludingDeleted()
    {
        /** @var DataObject|Hierarchy|Versioned $owner */
        $owner = $this->owner;
        $stageChildren = $owner->stageChildren(true);

        // Add live site content that doesn't exist on the stage site, if required.
        if ($owner->hasExtension(Versioned::class) && $owner->hasStages()) {
            // Next, go through the live children.  Only some of these will be listed
            $liveChildren = $owner->liveChildren(true, true);
            if ($liveChildren) {
                $merged = new ArrayList();
                $merged->merge($stageChildren);
                $merged->merge($liveChildren);
                $stageChildren = $merged;
            }
        }
        $owner->extend("augmentAllChildrenIncludingDeleted", $stageChildren);
        return $stageChildren;
    }