Bertha Mae Robertson, age 94, of Lewisville, Texas, passed away Friday, November 21, 2008, in Lewisville, of natural causes.  She was born June 23, 1914, in Denton County, Texas, to Joe Taylor and Mary Elizabeth Claiborne Taylor.  Bertha Mae married John Ray Robertson on February 20, 1932, and he preceded her in death on February 5, 1999.  She was a long-time member of West Main Church of Christ in Lewisville and worked as a beautician.  She is survived by her son, Floyd Robertson and his wife, Betty Ledbetter Robertson, of Double Oak, Texas; granddaughter Kimberly Robertson Head and husband, Don, of Keller; granddaughter Kayla Robertson Gannon and husband, Andrew, of Corinth; and great grandchildren Jake Gannon and Cameron Jane Gannon.  She was preceded in death by one son, Doyle Robertson, on November 22, 1994.  The funeral service will be held at 2:00 P.M. on Tuesday, November 25, 2008, at Mulkey-Mason Funeral Home in Lewisville.  Interment will follow at Chinn Chapel Cemetery.  Robert Archer will officiate the service.  The family will receive family and friends from 6:30 to 8:00 P.M. on Monday, November 24, at the funeral home.  The family requests memorial contributions be made to the American Diabetes Association.  For online condolences please go to www.mulkeymason.com.