Nature 26

Theo Albert Koster

March 12, 1941 ~ February 1, 2020 (age 78)


Theo Albert Koster passed away just after 7:30am on Saturday February 1, 2020 with his wife Brenda Johnston, his son Joe Koster, his daughter-in-Law Darlene Koster, and his daughter Jennifer Koster by his side.  His declining health due to complications from diabetes led to a weakening of his heart and ultimately his body was no longer able to go on.  Theo left this earth after a happy, full life, complete with the love of three great women, his two children, a step-daughter, eight grandchildren and two great grandchildren.

Theo was born in Den Haag, The Netherlands on March 12, 1941. He met his first wife Carla Slors at a party just before he was about to leave to serve in the Dutch military.   After an extensive period of letter writing (which he kept in a box for 60 years) the two would marry in 1964 and take a boat across the Atlantic to immigrate to Canada with nothing more than a couple of suitcases and $500.   They lived together in Hamilton, Calgary, Oakville, and Toronto between 1965 and 1982 before ultimately returning to Calgary to settle. They had two children together, Joe and Jennifer, and divorced in 1988.

Theo later met and married Lee Fulkerson, and she and her daughter Robyn would become a part of the family.  Through Lee, Theo would find a new career in oil and gas where he found some success and was able to build some wonderful new friendships. Sadly, their time together was cut short when Lee passed suddenly from cancer in 2001.

For the last 16 years, Theo shared his life with Brenda Johnston.  Together they enjoyed visiting Brenda’s family in Brandon, Manitoba, Logan Lake and Kamloops, and many trips to California and Holland to visit Theo’s.  They have many fond memories visiting and hosting the “Dutchies”, Theo’s sister Dineke and her husband Hans.  Their last big trip was to Vancouver Island in 2018 before Theo’s health started to decline. 

Theo worked hard to establish himself in Canada and built a career working with computers and technology in the banking and oil and gas industries.  Theo went to school at multiple points of his life to acquire and advance himself in accounting, information systems, and spent a period of time in commercial real estate. 

Theo was a Dutchman through and through.  He was stubborn as a mule, but he had the most kind and loving heart.  He was always there whenever he was needed and took great pride in supporting his children and grandchildren in their sports, business endeavors, and lives.  Theo is survived by his sister Dineke (Hans); his son Joe (Darlene); his daughter Jennifer (Ben); step-daughter Robyn; his wife Brenda and her children Tanis and Shaun (Sara); their grandchildren Jared, Carson, Tristan, Keira, Jyi, Veronica, Janie, and Emilia; and great grandchildren Maya and Adrienne. He will be missed immensely by all.

A celebration of his life will be held on Saturday, February 22, 2020 at 115 Mount Copper Park SE, Calgary, AB from 1:00 - 4:00pm.

In lieu of flowers, donations may be made to The Kidney Foundation. 


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The Kidney Foundation of Canada
Southern Alberta Branch 6007 1A Street SW, Calgary AB T2H 0G5

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