How does the monkey's paw ruin the White family?

The monkey's paw was cursed by a Fakir in India who wanted to teach a lesson to those who wished to alter their fate by asking for things which were not meant for them. The paw granted three wishes of its owner, but with it, brought evil consequences. Such a damage was faced by the White family in order to get their desire fulfilled.

The first and the greatest loss that the family went through was the death of Herbert, the son of Mr. and Mrs. White. They lost him after asking for their first wish of receiving 200 Pounds got fulfilled, but it cost them their son's life.

The second wish that the Whites asked for was the return of Herbert, but little did they know that the decayed and decomposed body of their son awaited their welcome. Mr. White had a premonition of this, so, to save his family from yet another misshapen, he quickly made his third wish and asked for Herbert's peaceful death. But although Mr. White had saved himself and his wife from any physical damage, his third wish cost him his marriage. By making his last wish, he caused great distress to Mrs. White, who was longing for his son's arrival, ultimately leading to a rift in their relation.

Although the drama has an open ending, but the breaking apart of their marriage could be seen as the possible damage that might have come along with the third wish. Hence, from the death of the only son of the house, to having an aghast experience and ruining the marriage, the monkey's paw left no mercy in shattering the White family.