Phoebe knew he was right but her family had had enough heartbreaks especially her mother who would only blame herself for Ruth being a monster. She had the evidence anyway and the house had talismans everywhere, her family members were safe. For now, it was better to wait and see.
Besides, how could she allow Ruth to leave so easily with a healthy body and all the money in her accounts? She had to be penniless and in pain. Now that the family didn't trust Ruth anymore, it was time to begin the second phase of her plan.
"David let's keep this between us at least for now, if she attempts to do anything then I will have to let them know."
They left and went back to the cemetery because it was time for the interment.