Coparcenary property revives on a son's birth, and post-birth alienations need legal necessity to bind the son's rights.

Property allotted to a sole surviving coparcener on partition remains separate in his hands only until a son is born; on the son's birth, the son acquires an interest by birth and the property becomes coparcenary property. Before that birth, the holder may alienate it as separate property, but after that birth any alienation must be justified as a karta's act for legal necessity. A sale deed or release deed executed without legal necessity cannot defeat the son's coparcenary rights and is invalid to that extent.

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Issues: Whether property allotted to a father on partition of ancestral property remains separate property only until the birth of his son and thereafter becomes coparcenary property, so that alienations made without legal necessity are void.

Analysis: Property received on partition by a sole surviving coparcener is separate in his hands so long as he remains alone in the coparcenary. However, when a son is subsequently born, the son acquires an interest by birth and the property assumes the character of coparcenary property. The holder could alienate it as separate property before the son's birth, but after the son's birth any alienation must be justified as being made by the karta for legal necessity. Alienations made otherwise cannot defeat the son's coparcenary rights.

Conclusion: The property became coparcenary property on the appellant's birth, and the sale deeds and release deed executed without legal necessity were illegal and void to that extent, in favour of the appellant.

Ratio Decidendi: Property allotted to a sole surviving coparcener on partition is separate only until a son is born; upon the son's birth it revives as coparcenary property, and any post-birth alienation is valid only if made by the karta for legal necessity.

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