It is with tremendous sorrow and much love that we mourn the sudden passing of Symeon (Simo) Mitsios of Whitby, Ontario, who passed away on October 13, 2026, at the age of 75. He was known for his honesty, integrity, and jovial nature. He loved his family, gardening, and his grandchildren’s smiles. He was the beloved husband of Eleni (Nanos) Mitsios for 48 years, loving father of Mary (Eric) and Daniel (Hilary), loving Papou to Thomas McDonald, Sophie McDonald and Konstantinos Mitsios, dear brother of Foti Mitsios (Jeannie), uncle to Christina Mitsios (Sam) and David Karat (Julia), and cherished friend to many. He was predeceased by his parents Konstantinos and Marika, father-in-law Athanasios, mother-in-law Iordana, and brother-in-law Anastasios.

He was born in Emporio, Kozani, Greece on December 19, 1950. After his father’s tragic passing when he was just 9 years old, Simo faced and overcame many struggles in his early life as the eldest son helping his widowed mother. As a teenager, he set out for a better life in Canada in 1967. He was supported by aunts and uncles, and later supported his mother and brother in their journey to Canada. It is in Canada that he met his wife, had two children, and built the foundations not only for his and his wife's life together, but for his children’s lives as well. Simo built a home of love, support, laughter, and joy. He had many warm and long-lasting relationships with cousins and friends. His biggest joy in life was becoming a grandfather in 2013, 2015, and again in 2024.

Simo spent the majority of his career as a manager in the manufacturing industry. He had a very strong work ethic and was well-respected by his colleagues. He also spent many years coaching his son’s little league baseball teams, leading them to championships.

The family would like to thank all of the medical professionals at Lakeridge Health Oshawa, Toronto Western Hospital, and Ornge ambulance services who provided exceptional and compassionate care during Simo's last days.

Simo will be deeply mourned and missed by his family and all those whose lives he touched.

Visitation services will be held on October 19, 2026 at 2-4 p.m. and 6-8 p.m. at Thornton Cemetery in Oshawa. The funeral will be held on October 20, 2026 at the same location with a visitation starting at 10 a.m., followed by a service at 11 a.m., and burial at 12 p.m.