My sister and I have a notarized temporary custody for.my nieces where she left me with custody of my nieces. I am financially supporting my nieces without any assistance frm both my sister or nieces' father. My mother has been saying rumors on how I can't take care of nieces because she wants custody of them. Can she be granted custody if I have notarized letter stating Iwas granted temporary custody and also have a school power of attorney letter notarized and signed by my sister?
Only a court can officially change the custody of your nieces. If you are concerned about your mother's actions, you should consult with a family law attorney to assist you in getting named their legal guardian.
Divorce / Separation Lawyer
If the children have been left with you then you can petition the court for custody. Your mother likely doesn't have standing to file suit. Beware she may elicit the help to CPS to get temporary custody. I'd speak to an attorney if you're truly concerned.