An internally displaced person (IDP) is a citizen of Ukraine, a foreigner or a stateless person who is in the territory of Ukraine on legal grounds and has the right to permanent residence in Ukraine, who was forced to leave or leave his place of residence as a result of or in order to avoid negative consequences armed conflict, temporary occupation, widespread manifestations of violence, violations of human rights and emergency situations of a natural or man-made nature (part one of Article 1 of the Law of Ukraine "On Ensuring the Rights and Freedoms of Internally Displaced Persons".
Therefore, your IDP status and benefits will not be affected by the fact that you will move in with your mother.
In addition, you can change the place of residence of an IDP in the "ACTION" application.