My Great Aunt and her family live in New Jersey. She is my godmother, so I want to invite her, her husband, and 4 children to our wedding. The 2 oldest girls are over 18 and still live at home. I have NO idea if they have significant others but it is VERY possible that they do. Do I need to call them and ask if they have a boyfriend before I send out invites? Do you think it's necessary to invite the SOs if they have them since it will be a family trip they're making to the wedding? Not sure if I'm making sense here, but I just want to follow proper etiquette before I hurt anyone's feelings.
P.S. Would my great aunt's children be my second cousins? They are my grandmother's sister's children.