Almost a third of claims were/are denied. Some brought up interesting alternatives, but even those alternatives, could have been the result of revenge, but I think this graph tends to lend a degree of credence to the revenge of a loved one lost because of a claim that was denied.
A loved one lost, that was perceived that they could have been saved if the insurance coverage had not denied the claim, can be motivation for revenge regardless of age. A child probably raises that likelihood considerably, without question.