David Dental, DDS, and his unmarried partner Sally Surgeon, MD, have lived together for the past five years. Both are at the peak of their carrers and decide to buy a new "showcase" home in La Jolla, California. After looking at several homes in the area, they buy one for $2 million. They put a 20 percent down payment (400,000 on the house and finance the balance $1.6 mil) Each take out a separate mortgage for $800,00, for a total of 1.6 million. There is additional debt (e.g. a home equity loan on the residence. Locate the chief counsel advice (CCA) that deals with this situation. Give the CCA citation.