Hi, I am using on publish notifications but have noticed when we do publish with descendants it doesn't seem to send these descendants through the custom on publish notification. Is there something I need to enable for this?

Could it be that publish with descendants don't trigger notifications? If so you probably can't do much - could try to switch to the ContentCacheRefresherNotification instead as that may trigger

Does the descendants have any changes or are they already published? I believe Umbraco won’t trigger a publish a descendant if it’s already is published and have no changes