Help need

[Drewkidd68]

Hi, my father died in late 2013 when I was 13, I'm currently 17 and after finding his will I have found out I have a half-sister who is 16-17. I would like to contact her, however, I've been told I wouldn't be able to by my mother due to some legal rule. I'm not convinced, is there a law that stops me from contacting her? Or do I have to wait until we are both 18?

Thanks in advance, any comments would be appreciated.