How should Islam treat a committed person whose mother disbelieves in God and curses the religion, and is she excused by the impediments to excommunication (takfir), and is there a difference in treatment between righteous and disbelieving parents?

The ruling on insulting Allah or religion is disbelief (kufr), whether done in jest or seriously. Whoever commits this act is a disbeliever. However, judging a specific person as a disbeliever and applying the associated rulings to them requires the fulfillment of conditions and the absence of impediments. One whose Islam has been established with certainty does not lose it except after the establishment of proof (hujjah) and the removal of ambiguity (shubhah). It must be noted that the application of prescribed punishments (hudud) is only carried out by the ruler (sultan).