Firstly, forgetting the visa of your kids is unpardonable, however, lets imagine ourselves in vijay and vaishali's situation...what can one possibly do once they've realised they've missed some important documents? Well, you obviously don't want to miss your flight and lose on the expensive tickets you purchased, so you take the flight and deal with the consequences then..So, vijay and vaishali did the right thing..the fax approach was also right, however, the immigration officials should have given them atleast a decent amount of time to prove their point..Do we have a law which allows/ restricts the number of hours a person can be at the airport without proper visa documentation? If not, we need a law which helps us with the same. Vijay and Vaishali, you guys have learnt a lesson for life and a quote from bhagwad gita for immigration officials - "Perform your obligatory duty, because action is indeed better than inaction", however make sure that your duty was 'obligatory' at first place and just don't misuse the powers because you have them.