Children born out of marriage Sirri has a different position with children from other marriages. Son ofmarriage Sirri, in the perspective of religion is legitimate, but legally is not recorded in the Office ofReligious Affairs. The existence of child in the marriage Sirri must get legal certainty and the protectionof law. Decision of the Constitutional Court (MK) has provided certainty and legal protection, but ina religious court the verdict has not been granted a constitutional manner. Therefore it is necessary toreconstruct the inheritance law of children born out of marriage Sirri by incorporating Court decisionNo. 46 / PUU-VIII / 2010 as a source of law in the legal system of inheritance in religious courts. Lawshould provide protection and legal certainty to the status of a child born out of marriage Sirri andrights available to him, although the validity of the marriage is still in question.