John Gregory Cook of The Villages, Florida, died after a sudden, unexpected illness of acute leukemia on Friday, December 13, 2024 at his home, surrounded by his family.

He was born in Quincy, IL on December 7, 1947 to the late Waldo and Rita (Kathman) Cook.  He graduated from University of Illinois with a Bachelor of Science in Physics in 1969.  He received his Master of Science in Nuclear Engineering from University of Illinois and his MBA from Golden State University.  He married Marjorie Wisman on June 13, 1970 and they have three children, Rob, Jennifer, and Eric.  They were happily married for 54 years.

John lived a very full life, both personally and professionally.  In 1970, he was a Lt. USNR at the US Naval Nuclear Power School at Mare Island Naval Shipyard where he served as an instructor.  After serving in the Navy, John moved back to Illinois with his family to live in Maroa, IL and to work at Illinois Power, where he served in several roles, including Plant Manager of Clinton nuclear power plant and Senior Vice President of Illinois Power.  John then worked as a mentor for nuclear plant managers at the Bruce nuclear plant in Ontario, Canada for two years. In 2000, John and Margie moved to Vienna, Austria where he worked for the International Atomic Energy Agency (IAEA) as team leader for numerous nuclear power plant safety inspections (OSART) around the world.

John was a devoted husband, father, and friend, who faithfully served his community wherever he went.  In addition to volunteering for his church and his children's sports and activities, John also served on the Maroa-Forsyth School Board.  While living in Maroa, John and Margie hosted three exchange students.  He was known as a Renaissance man who excelled in the arts as well as math and science.  He loved to take pictures of nature and loved ones and paint these images using oil as his medium of choice. He also loved a variety of sports, card games, and everyone admired his incredible knowledge and love for trivia.

John is survived by his wife, Margie, his siblings Robert (Fran) Cook, Victoria (Frank) Krueger, Jim (Bernie) Cook, and Betsy (Ken) Smelcer, in-laws Jeanne (Tom) Behrensmeyer, Tom (Sachi) Wisman, Nancy (Mike) Quoss, Jim (Anabel) Wisman; his children, Rob (Emily) Cook, Jennifer (Dennis) Ellison, Eric (Jenni) Cook; exchange students Else Fredriksen, Jan (Constanze) Rémi; grandchildren Ross Cook, Will Ellison, Lili Cook, Evan Cook, Chloe Cook, Katie Ellison, Maia Cook, and many nieces and nephews.  He was preceded in death by his parents, his grandchild, Sarah Ellison, and his nephew, Michael Wisman.

Military Funeral Honors are scheduled for December 30, 2024 at 12:30 PM at Bushnell National Cemetery. In lieu of flowers, memorial donations may be made to World Vision or Cornerstone Hospice of The Villages, FL.  A celebration of John's life will be held at a later date.