Human thinking....

I was going home after office and suddenly something fell in one of my eyes...i stopped on one side and tried to find what fell in my eye which has created so much of burning ....i couldnt find anything..but it was burning horribly....as a sympathy my second eye also started weeping/watering....if one eye is in trouble,the other eye also expressed its grief and showed that it is there in thin and thick of life.....what bothered me was why we humans are not like that...we hardly find a sibbling feeling sad when his/her other sis/brother are in trouble.They belong to same family..they share same blood...still no sympathy for eachother...if we expand it to society...we share the same society...but how far we are with it...what are we doing by being in the same brotherhood...I feel sorry for my/our own behaviours and resposibities we share towards our family or society...