Based on the limited facts you have provided, there is almost certainly no negligence claim against the second wife. She is not liable for the criminal or negligent acts of the third parties. With regard to the life insurance beneficiary change, if the change was properly made and there is no evidence that either he was fraudulently induced to make the change or misled as to the state of affairs with regard to the change of beneficiary, then you likely have no claim on that aspect as well.Additional facts may change these responses as your question is sketchy in many key details.
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