Posting Photos

Mamas who don't allow photos of their children be posted on social media how did you have that discussion with family? My family is already aware that we have decided not to have photos of our child posted on social media. That was an easy discussion because it was my family and I don't care to piss them off 😂. Now my husband's side is a different story I have not mentioned it to them and they are all the type that posts every waking moment on Facebook. I want to have the discussion without coming off as a bitch or that I am keeping our son from their family. Also have you had someone post without your permission? How did you handle that situation? I am currently 37 weeks and feel like I need to have this discussion before he arrives.