It’s long past time for a major confrontation with your sister. She has had a child but that doesn’t make her a mother. Mothers don’t make a 10-year-old into a bodyguard. Mothers don’t act less adult than their kids. Of course the child is stressed out. Of course she is showing it physically. She’s trapped. She loves her mother but she’s scared.
Your niece can’t take her mother on but you can. Tell your sister that if she doesn’t clean up her act and take care of this child as she should, you’ll call protective services — then do it. It’s not doing your sister any favors to allow her to throw her life away. It’s not being a responsible aunt to watch your niece be victimized by her mother’s behavior.
If your sister can’t step up and deal with her alcoholism and irresponsible behavior, I hope you have it in you to tell her to leave and to take on raising this little girl by being a designated foster parent. I hope there are other family members who can help. Please don’t be frightened of protective services. They really can provide services and guidance when a family works with them.
I understand that going forward this way is very, very hard. It’s not fair that you are in this position. It’s not fair to your niece to let it continue. But taking charge may save your sister’s life and will certainly reduce the child’s stress and perhaps give her a brighter future.
I wish you well.