Hello Melanie, my name is ***** ***** I am a licensed psychotherapist in private practice in New York State. Thank you for reaching out to Just Answer with your concerns about your younger sister. Firstly, it sounds like she has terrible boundaries regarding your mother's rights and her other's sister's rights. Can you please tell me ho wold she is and a little bit more about her? Does she live with your mom, does she work, is she in a relationship, does she have any personal issues she struggles with, etc. Thank you. The more you can share with me the more I can understand what she may be bringing to the family relationships and be able to guide you. I look forward to hearing from you. Sincerely, ***** ***** LMSW, CASAC
Thank you for the additional information and for waiting for my response. I am going to give you the criteria for Borderline Personality disorder and I am wondering if you could tell me if this sounds like she has some of these traits:
Seemingly mundane events may trigger symptoms. For example, people with BPD may feel angry and distressed over minor separations—such as vacations, business trips, or sudden changes of plans—from people to whom they feel close. Studies show that people with this disorder may see anger in an emotionally neutral face and have a stronger reaction to words with negative meanings than people who do not have the disorder.
Okay that is good, then given what you have said your sister may have really poor boundaries. Of course, it is impossible to diagnose a person without having several face to face sessions with them, but she does sound like she has very loose boundaries in her relationships. Individuals who have poor boundaries as adults are usually people who as children got lost in the family dynamics and did not develop a true sense of their own integrity, beliefs, values, etc. It is important that you or all of her sisters let her know that her behavior toward your mother is unacceptable to all of you, and the expectations you do have. She needs to hear this. If she can't accept it then you all have to come up with a plan to support your mother in dealing with what she does or says to her. Does this make sense?