"OCI card needs to be re-issued each time a new passport is acquired by the cardholder up to the age of 20 years."
However if a minor child enters India on OCI & valid passport:
1) Is there any need for minor to renew expired passport if no travel is intended outside india ?
2) Does the child become illegal in India if passport expires ?
3) In other words, is it necessary to renew passport and renew OCI for a minor under 20, to maintain valid legal stay in India even if no international (outside india) trip is on radar ?