Wednesday of last week Gordon E. Mordoff Jr., 2119 Birchwood ave nue, was appointed by John F. Keeley, assistant to the Probate judge, as administrator of the es tate of the late Dr. Gordon E. Mor doff, who was slain in Wilmette on January 12 by his brother-in-law, John P. Quinn. The estate is esti mated at $15,000. Miss Mary Mordoff, who was raised by Dr. Mordoff as his daugh ter, opposed the appointment of Gordon Jr. on the ground that he was also an adopted child, which he denied, asserting that he is the real son of the dead physician.