O'BRIEN, Walter J. Of Lexington, Sept. 13, 2017, age 95. Beloved husband of Mary J. (McGowan) O'Brien. Loving father of W. William of Lexington, Robert J. of Hampton, NH, Erin M. O'Brien of Beverly, Richard J. and his wife Cheryl of Billerica and Stephen E. and his wife Anne of Nashua, NH. Cherished grandfather of 8 grandchildren and 3 great grandchildren. He is predeceased by 8 siblings. Also survived by many nieces and nephews. Funeral Services will be held at the Douglass Funeral Home, 51 Worthen Rd., LEXINGTON, on Monday, Sept. 18 at 10 a.m. Relatives and friends are kindly invited to attend. Visiting hours at the funeral home on Sunday from 2-6 p.m. In lieu of flowers, donations in his memory may be made to St. Jude Children's Research Hospital , 262 Danny Thomas Pl., Memphis, TN 38105. Interment Pine Haven Cemetery, Burlington. Late Veteran U.S. Marine Corps , WWII .