We don't discuss names with other. My younger sister wouldn't tell me the name she had picked for a girl (she was due 4 months after me) until after we found out we were having a boy. Lol. I wasn't offended. She was just very protective of the name!! But I don't think anyone, family or friend can put dibs on a name if they decide to start talking names with you.
We don't tell anyone names until baby is born and then that IS there name. No changing it, no opinions.