Inappropriate use of digital media

My sister takes things she sees on facebook and shares them even though they offend.  She is blatant about her statements and it has caused friction and tension between extended family members.  I have talked to her in person about why the shared item is offensive, and sometimes she will take the post down, but the damage has already been done.  I don't think she would bring the topic up so boldly in person and thus is throwing things out there and hiding behind a computer while doing so.