I realize now that was a great mistake.In the medical request letter it was stated to send passport copy , so my parents send only passport copy with medical receipt.Then , after 4 weeks CHC requested to send original passports. Now there is some problem with some nos on the envelope(VFS thing, I believe, not sure though) , so they rejected the passports, now we have to get passports back and send it again. What a waste of time!