Wedding

...My sister was angry about our family not being invited to my brother's marriage on May 10th. She invited our whole family to her wedding in 2004. She hasn't told me her husband and her are going to be in attendance but she hasn't denied it either. I waited three weeks after my sister got emailed news of the wedding date to get something from someone. Nothing. My mom is having the wedding on her property. Its not about me(the adoptee)being rejected...its our whole family. Can anyone help?