First of all, the relevant materials of your mother's origin: the neighborhood Committee issues the certificate of permanent residence, and the subordinate police station issues the household registration certificate and household registration book; The neighborhood Committee where you live now issues a certificate of permanent residence, a house lease contract, and a number of one-inch bareheaded photos (I forgot specifically, at least eight), and then it is enough to hand them over to the household registration police in the jurisdiction. It can be done in three months if the general materials are all right. I suggest you go to the household registration section of the police station to ask for relevant application materials.
I hope I can help you.