The immigration officer was really very difficult.    'Why do you want to visit your grandchildren?'  The answer seemed obvious.   If I don't come to s f then I won't see them.    I like to keep in touch.    But he was really having a bad day, so he asked again:'Why do you want to visit your grandchildren?'   So I thought may be he wants details.    This time i am here because my son has just adopted a little Vietnamese girl, so  I am here to see my newest granddaughter!   And that was enough.   He grudgingly let me pass and go down to the meeting hall where my famiy were standing waiting for me.