How To Reply Privately in Social Inbox
Social Inbox gives you the option to reply privately to people commenting on your posts. This is particularly for information that is confidential or should only be shared with certain people.
Through Social Inbox, you can reply to them privately through the comment section. Reply as private option is located just beside the reply option.
Note: You can only reply privately on comments no older than 7 days. Comment older than 7 days will not show the option to reply privately. Also, Facebook allows you to send private messages only to people and not other pages. So, if another page is interacting with your post, you can not send them private messages.