What is the share of each heir from the inheritance based on the mentioned information?

If the heirs are limited to the husband, the son, and the mother, then the husband inherits one-fourth due to the presence of a lineal descendant, and the mother inherits one-sixth also due to the presence of a lineal descendant. The remainder goes to the son by residuary right (ta'sib).

The inheritance is divided into twelve shares: three for the husband, two for the mother, and seven for the son. The two grandmothers and others are completely excluded (mahjub hirman).

It is advisable to refer inheritance matters to the Sharia courts, as there may be issues unknown to the heirs, such as bequests (wasiya), debts, and rights, which take precedence over the rights of the heirs.