Neglecting a child's emotional needs can be considered a form of child abuse in some jurisdictions. Emotional neglect can have serious and lasting effects on a child's well-being and development. Emotional abuse or neglect can include actions such as constant criticism, rejection, or withholding love and support.
The incident you described where your parent made a concerning statement about keeping your little sister alive after being upset that she wouldn't talk could be considered emotionally harmful. If you are worried about your sister's well-being or believe that she is experiencing neglect or abuse, it may be appropriate to seek help from Child Protective Services (CPS) or a similar child welfare agency in your area.
CPS agencies are responsible for investigating reports of child abuse or neglect and taking appropriate actions to ensure the safety and well-being of the child involved. If you are unsure about whether to make a report, you can reach out to a trusted adult, teacher, counselor, or a helpline dedicated to child protection for guidance.
Remember that it's essential to take any potential signs of abuse or neglect seriously, as the safety and well-being of the child should always be the priority. If you or your sister are in immediate danger, don't hesitate to call emergency services or the appropriate authorities in your area.