A man marries a woman,They become two,The woman delivers a baby,They become three.The woman delivers another child,They become four.The baby becomes a boy and he goes to school.He has five friends.Now they become nine.The child becomes a  young girl and goes to school too.she gets six friends,Now they become fiteen in all.They all come to the birthday party of the boy,Now, Can you tell meHow many were present in the birthday party?