Your right to take down the pictures may depend on where exactly the picture was taken, and it sounds like you can legally ask them to take them down. The reason is that as a property owner, you can prohibit a photograph being taken in your home (or other places where you have an expectation of privacy). Since it sounds as if the photographers actually came into your home and took the pictures, and you did not consent, you should be able to get the photos taken down.
Of course, the simplest method is to ask the uploader to remove it (or to at least make it private), but I assume they have refused. Talking to the uploader and explaining your problems is usually the best way in most situations. If you believe that contacting them won't help in this case, you can "Report" the photo, explain the situation, and Facebook moderators can take a look at it and take action depending on their own judgment and guidelines.
It depends. If your children are under 13, it looks like Facebook has a procedure:
How can I get an image of my child removed?
Facebook removes content that violates the Facebook Terms, based on laws in specific jurisdictions. Use the Report link located near the photo or video t...
Facebook removes content that violates the Facebook Terms, based on laws in specific jurisdictions. Use the Report link located near the photo or video to report the abusive content to us. Facebook offers additional privacy safeguards for people under the age of 18:
Under 13 years old – Please submit a request to have the photo or video removed. We will review the content and remove if it contains an image of your child, he or she is under 13 years old, and you have filled out the report form accurately and completely. Please understand that we can only take action on reports that come from a parent or legal guardian of the person pictured.
Between 13 and 17 years old — We can’t help you directly unless required to do so by law. Please ask your teen to submit a request to have the photo or video removed.
In the latter case, you might consider the angle suggested by the other attorney - pictures taken in a private location without the permission of the owner of the premises. If you have a good relationship with your children, you might explain to them why you (and they) might not want their photos posted. Otherwise, it can get complicated.