is it ex party and you donot aware of this divorce petition? also talk to the advocateof coimbatore. but before sending money check the genuinity of the person.
though coimbatore is far but better to send your sister/ the said wife to there. it will not much costly. must take photographs and other documents which prove the marriage. how you came to know about the divorce?
you may also contact the local mahila thana and claim the maintenance against the husband. against your complain police will lodze a case and started finding the person, his whereabouts, and will call him. in case of absence he will be under arrest by your local thana, - the whole details you will get by sitting in your room.
but if you received notice and did not appear, then, this will not effect.