I am glad her cousin and that side is in Europe I hope she is stateside.
Does her mother know about what the Aunt did?
I kindof feel, she will need to sever ties with that side till the appropriate time of if and when to tell the child.
I wonder if she could talk to her cousin? Tell her the issues and if the mother does not "cease and desist" they will need to part ways for a while so that she can get on her feet with this new baby etc.
It is most important that if a person is tell that it is up to them that goes without saying, where and when and if.