Not all foster kids come from the same ethnic backgrounds. So for example if you're Caucasian and post a picture of your family with a foster child who is Asian, or African-American etc, it can bring unwanted attention.
Not saying you're wrong at all, I have zero insight into foster care. Just trying to understand.
But why is it a problem if someone sees a family photo and notices that one kid looks different? He could just be adopted, or a friend or something. Is it something like witness protection, the children might have abusive parents that shouldn't be able to find them?
If it's a matter of not standing out, they will stand out just as much when you meet them anyway, right?
The number of people you meet in person is limited by geography. The number of people who might view a photo online is 7+ billion.
Foster kids might have abusive parents as you surmised. They might have been removed from an unsafe home, or have relatives that were denied custody and might act on a photo.
