Is it permissible to make an ongoing charity (Sadaqah Jariyah) for a deceased mother from the son's private money, given that there is an inheritance that has not yet been distributed?

There is no harm in giving charity on behalf of a deceased mother, whether from the son's private funds or from her estate. Scholars have agreed that the reward of charity reaches the deceased and benefits them. This is supported by the hadith: "My mother passed away suddenly, and I think that if she had spoken, she would have given charity. Will she have a reward if I give charity on her behalf?" He said: "Yes." The imams also agreed that charity reaches the deceased and that endowments on their behalf benefit them. It must be noted that it is not permissible to give charity from the share of another heir without their permission.