This was explained in the letters. The kids decided to drop their lawsuit after receiving the letters.
They accepted that their mothers did not deserve any of the inheritance and realized how badly they had treated them. Even though Cassandra never met the sisters’ children, she noticed that each year on the anniversary of their deaths, fresh flowers were placed on their graves.
Knowing that the sisters’ children were finally honoring their mothers, even if it was too late, comforted her with this small act.
