How can the legitimate lineage of a girl born from an unregistered marriage be proven, given that the father and all those who knew of the marriage have passed away?

The facts of the case demonstrate the wisdom of Islamic law in stipulating the guardian (wali) and witnesses for marriage, and the importance of its announcement, for the establishment of lineages and the prevention of disputes. If there are no means to prove lineage, there is no harm in resorting to DNA testing in cases of dispute. The Islamic Fiqh Academy has permitted this, as stated in the resolution of the Council of the Islamic Fiqh Academy during its sixteenth session held in Makkah al-Mukarramah: "It is permissible to rely on DNA fingerprinting in the field of proving lineage in cases of dispute over an unknown lineage." It is important to be aware of the serious danger of challenging and denying lineages after they have been established, due to the severe warnings mentioned concerning this.