How is the ransom value for the child born to the usurper determined?

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The ransom for the child should be determined by their value on the day of birth, as this is the first time their value can be assessed. A narration from Al-Kharqi suggests ransoming them for their equivalent (in age, description, gender), which Ahmad endorsed. Abu Bakr 'Abd al-Aziz suggested ransoming them for their equivalent value. A third narration from Ahmad, which is the most sound view according to the author, states they are ransomed for their market value, similar to other properties that are not standardized goods (Mithli), as they are guaranteed by their value if destroyed.