In loving memory of Dad. John D. Knollenberg, 87 formerly of Boulder passed away Saturday, October 8th, 2022. A native of Mattoon, Illinois, he was the son of William Knollenberg Jr. and Hellen Eleanor (Kastl) Knollenberg. John married Christina (Salvetti) Knollenberg December 28, 1963 in Peoria Illinois and were husband and wife for over 53 years. Together, they had three children: Brian (Janice), Perry (Oanh) and Sally (Kurt). John is survived by his three children as well as five grandchildren and five siblings. He was preceded in death by Christina, his parents, nine siblings and one grandson. John served as a naval aviator in the 1950s and 1960s and was a life long commercial and private pilot. Over the years, he worked as an educator and engineer in Illinois and Colorado.