I think this is one of the reasons we should fly Air India. You get the desi flavor right from the beginning of your flight and this would have ensured that you did not forget your visa. They are very good at finding out such errors as well as issues in documents that are perfect.
I have visited the US multiple times. However, I never knew that they issue transit visas to Indians on arrival in the US !! So I guess there is one more democratic country besides India which does not issue such visas. I can empathise with the children's plight but unfortunately, this can't be written off as a simple "human" mistake when undertaking international travel.
