Yes! Grandparents and other relatives can save photos/videos as well as delete their own comments by doing the following:
・App Version: Open the Album tab and tap a photo or video. Tap the menu icon in the top-right corner, then tap "Save."
・Browser Version: Click a photo or video, then click the "Save" button.
*Grandparents and other relatives can only delete their own comments.
・App Version: Tap and hold a comment to edit or delete it.
・Browser Version: Click the X button next to a comment to delete it.