Abnormal behaviour. Is threat for all.

Appears personality disorder, all other family members should set disciplined behaviour in the family, be strict with her if she does not follow. She would know other family members are loving her, they may not be strict with her. She may be emotionally blackmailing....be assertive otherwise u guys may not handle her

She needs counseling. A counselor can talk to her and find out the reason for her stress and anger and help her through guidance and lifestyle changes. I am an online counselor and can help her too . Do connect with me if required. Visit my Facebook page and my website mentioned on it to know my work. Happy to help !

Hello Friend, Good that you are seeking a help here. Behaviors with anger, frustration, argumental, irritation, Mood swing, hurtful speech etc are expression of stress or outburst of stress in mind or lifestyle. Sometimes bodily condition like excess heat in body, PMS, thyroid issues, acidity etc also can trigger and influence such stress. As body and mind are interlinked it can affect each other. Be positive. Just observe and analyze what's happening in personal and professional life. May be work related tension or relationship issues could be triggering such behavior. She may need some counselling guidance to cope with such stress levels and control emotions over loved ones. Be positive. She will be alright soon. Feel free reach me online for further evaluation and recommendation.