Cover photo for Mary A. Theriault's Obituary
Mary A. Theriault Profile Photo
1963 Mary 2023

Mary A. Theriault

January 28, 1963 — July 26, 2023

Orland Park


Mary Ann Theriault, 60, passed away peacefully on Wednesday, July 26, surrounded by her family.

Mary was born on January 28, 1963, to Margaret and William Steinert in Chicago, Illinois. She grew up with older brothers Dan and Bill, and older sisters, Judy, Nancy, Donna, and Bonnie. As the years went on Mary gained sister-in-laws, Sharon and Karen and brother-in-laws, Gus and Terry.

Mary met the love of her life, Don, in high school and they were married on August 4, 1984. Mary and Don were true high school sweethearts. Just like in present day, their favorite date night included dinner and a movie—sometimes two movies in one weekend!

Mary had various jobs and titles throughout her life, but “Mom” was definitely her favorite. When Don and Mary decided to start growing their family in 1987, Mary knew she was meant to be at home raising her children. In the coming years, Mary and Don welcomed their four daughters Danielle (35), Sarah (33), Rebecca (31), and Lisa (25). Their four daughters were Mary’s absolute pride and joy, and they defined her true purpose in life. However, her daughters were not the only recipients of her affection. Mary also had an extreme love for all animals, especially dogs. As far as we can remember, there was always a dog present in the house growing up — Shelby, Elvis, Brutus, Duke, and Winston. They also brought her so much joy and purpose.

As the girls grew older, each one met the love of their life (Tony, Marcus, Jeremy, and Ian) and began to grow their own families. This meant that Mary was able to welcome and spoil eight grandkids, which was her absolute favorite. Rylan (9), Anthony (7), Jaxon (4), Theodore (4), Trevor (3), Cameron (2), Shane (2), and Riley (1 month) loved their Grandma immensely. Mary’s favorite thing was to spoil her grandkids and always made sure they felt loved.

Mary put her heart and soul into everything she did—especially family gatherings and celebrations. Every birthday party and holiday was filled with games, entertainment, food and surprises. Mary looked forward to family gatherings and always outdid herself. From spoiling her daughters, nieces, nephews, and grandkids with an unthinkable number of presents, to coming up with fun games, she sure knew how to throw a party! Everyone always left feeling full, loved and fulfilled in the best way possible.

This past year was a true testament to Mary’s fighting spirit. However, after a heroic fight to overcome a diagnosis of stage III pancreatic cancer, her body was too weak and could not withstand further treatment. Her fight did not slow her down. She continued to show up for her family and her grandkids with every ounce of energy she had, even in her final days.

We find comfort in knowing that Mary is now in Heaven with those who preceded in her death, parents Margaret and William, and sister, Bonnie. She is no longer suffering and has taken on an even more important role for her family—guardian angel.

In lieu of flowers, the family requests any donations in Mary’s honor be made to support the NAWS Humane Society ( Mary’s love for animals was prevalent throughout her life and she made this special request in her final days.


To order memorial trees or send flowers to the family in memory of Mary A. Theriault, please visit our flower store.

Service Schedule

Past Services

Celebration of Life

Friday, August 11, 2023

4:00 - 8:00 pm (Central time)

Blackburn, Giegerich, Sonntag Funeral Home

1500 Black Road, Joliet, IL 60435

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