On page 688 mr.whiteman attributes the first with his sons death as a coincidence if he believes this why does he fight with his wife about not using the paw again?

He does not think of his son's death as a coincidence; he fights with his wife about using the paw a second time, but he gives in to her because of her grief and desperation. He realizes once the second wish has been made that there could be a real problem since the body has been in the ground and decomposing. He makes the third wish to send Herbert back to his grave knowing that they would have to deal with their grief, but that could be better than the other alternatives.