Annie James died early in 2014. All her property passed subject to her will, which provides that her surviving husband, Dave James, is to receive all the property outright. Her will further states that any property Dave disclaims will pass instead to their children in equal shares. Annie's gross estate is $6.3 million, and her Sec. 2053 deductions are $300,000. Dave, who is in poor health, already owns about $5 million of property. What tax issues should Dave James consider with respect to the property be quested to him by his wife?