Kingdom of Jerusalem

Queen Isabella has a son by her third husband, Henry of Champagne. He survives to adulthood. Who succeeds? Her daughter by Conrad of Montferrat or her son?
 
Of al the medieval Kingdoms Jerusalem had the least clear succession laws because the constant military pressure and deaths meant no clear long term precedent could be set. So it's possible that an adult daughter with a militarily capable husband would have priority over an infant son. But in all certainty a son would be the heir.
 
Queen Isabella has a son by her third husband, Henry of Champagne. He survives to adulthood. Who succeeds? Her daughter by Conrad of Montferrat or her son?

As it was said by others, it really heavily depends of the context.

Fort what it's worth, you could even end with a split of yerosolemite kingship, or that neither of them inherit the throne, or probably that the husband of Isabella is crowned (critically considering it was one of the main reason she was married to Henri de Champagne or Amaury II)
 
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