Patricia A Mitchell, of Wellesley, Watertown and Hyde Park, MA. Passed away peacefully after a long struggle with dementia. She was 87 years old. Beloved wife of deceased Donald C. Mitchell, mother of Carole Katz of Watertown and Bruce Newman and his wife Ellen of Walpole.  Devoted grandmother of Kim, Jennifer, Katie and David.  Great-grandmother of Kenzie, Sean and Tinsley.  Patricia was the last remaining of seven O'Brien siblings:  Ernestine, Teddy, Bob, Jerry, Marie and Joan.  She had many devoted nieces, nephews, grandnieces, and grandnephews. Patricia worked in the accounting division of the MBTA for many years and later went on to work in banking at Baybank, Hyde Park Savings and Dedham Savings Bank.  Her greatest enjoyment was in helping others whether it was assisting customers with their finances or helping to raise her four grandchildren.  She raised Carole and Bruce for many years on her own until she met the love of her life, Don.  With him she began to truly enjoy life.  They spent many years together as a family boating, skiing, and traveling.  After Don's death she continued to enjoy traveling with her sisters and later with her daughter.  A memorial service will be planned in the future.  Patricia will be interred next to her husband at Arlington National Cemetery. In lieu of flowers donations can be made to the Grow Clinic at Boston Medical. https://www.bmc.org/programs/grow-clinic