Chen Stevenson died at the age of 85 leaving behind all his property to Phillip Miller, his butler. The news of the new will that Chen executed three months before his death naming Phillip as the sole beneficiary surprised everyone. By his prior will, he had bequeathed his estate to his two daughters and three grandchildren on a per capita basis. The court took up proceedings to determine the validity of his new will because Chen's rejection of his daughters and grandchildren in his will was uncharacteristic of him. The court most likely suspected this change to be a case of ________.

undue influence

spendthrift trust

undue hardship

constructive trust