Patricia Jo Cosand-Chesterfield, lovingly known as PC, was born on December 9, 1964, in Helena, Montana to Dudley and Carol Cosand. She passed peacefully in her sleep on February 17, 2026.
Pattie spent the majority of her life in Great Falls, Montana, where she built lifelong friendships and deep family roots. She married Pat Chesterfield, and at just 19 years old welcomed her only child, Jennifer Marie Chesterfield, in 1983 — the greatest joy of her life. In 1988, Pattie met her true love, Ronald DeWitt, and the two shared more than 20 wonderful years together, building a life full of laughter, adventure, and devotion.
Family was everything to Pattie. Not only did she raise her beloved daughter Jennifer and daughter in love Jessica Chriswell, she also helped raise Danny and Michael DeWitt, as well as Ryan and Christena Bruno, loving each of them as her own. She was later blessed with grandchildren and great-grandchildren, cherishing every moment she could spend with them. In a rare and beautiful chapter of her life, five generations of women shared time together: her mother, Carol, Pattie, her daughter, Jennifer, her granddaughter, Mystika, and Mystika’s child XX — a legacy Pattie held close to her heart.
Pattie was never afraid of hard work. She discovered her passion tending bar, where her quick wit and warm personality made her a favorite to many. She later spent many dedicated years working at CUC and gave generously of her time volunteering for the Center for Mental Health, always ready to lend a helping hand to those in need.
She loved the outdoors and found peace tending her yard and vibrant flower beds during the warm summer months. The yard was never more beautiful than when Pattie poured her love into it. Beyond gardening, she embraced life’s adventures — camping and spending time at the family cabin in Lincoln, car cruises and poker runs, riding ATVs and snowmobiles, and enjoying vacations and cruises with family and friends.
One of her favorite traditions was the annual Black Eagle Country Cruise, where she was known for making jello shots, organizing the poker runs, and selling 50/50 tickets — always with a bright smile and contagious laughter. Pattie lived fully, loved fiercely, and created countless memories that will live on in the hearts of those who knew her.
She was preceded in death by her parents, Carol and Dudley Cosand and her brother, Alan Cosand.
Pattie is survived by her boyfriend of many years, Bill O’Keeson; former partners, Ronald DeWitt and Pat Chesterfield; her daughter, Jennifer Chesterfield (Mystika, Trinity, Tristan) and daughter in love, Jessica Chriswell; her stepchildren, Danny and Michael DeWitt; and several treasured great-grandchildren (Liam, Grayson, Malailah), along with many extended family members and dear friends.
A memorial service will be held at 1 pm on March 27th at O'Connor Memorial Chapel (2425 8th Ave N, Great Falls, MT 59401) for close family and friends, followed by a celebration of life open to all at the Black Eagle Country Club (1126 Smelter Ave Black Eagle, MT 59414). All who knew and loved Pattie are welcome and encouraged to attend.
Pattie’s legacy is one of strength, laughter, generosity, and above all, love. She will be deeply missed and forever remembered.
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