Trey, I am not sure where I saw it, but daughters were not included.
As far as protection, I think it goes back to Rene De Anjou and protecting the minions under him and his lands.
The Badge is given only to those who desearve to wear it, such as members or those who will be betrothed to that Brother.
Maybe it would be easier if the daughter wore a sign, "My Dad Is A LXA". "Mess With Me and Hell will Rain on Your Parade"