So, this comes from a post on facebook. This woman wants to change her DD's last name. The DD has her BD's last name. BM wants to change the DD's last name to that of SF because BM wants their entire family to have the same last name. The BM is trying to figure out if she can legally change her DD's last name without having to notify the BD.
I can't tell you the number of people who are telling her it's totally OK to change her DD's name without notifying the BD and without his permission.
It makes me so sad that people are so quick to dump the OP from their child's life to make their OWN life easier.