David Keller Mack passed away peacefully in Laguna Woods, California on February 17, 2023. He is survived by his wife of more than 57 years, Sharon Mack, along with three children and five grandchildren. David was born on December 23, 1941, along with his twin brother Dick, in Louisville, Kentucky. His  parents were Grace Melinda Smith Mack and Dr. John Keller Mack (who went by Keller, named in honor of his relative, Helen Keller). David is survived by his sister, Phyllis Reynolds, who lives in Evanston, Illinois, and is exactly 3 years, 3 months and 3 days older than her brothers. Dick passed away on October 18, 2020, in Newburyport, Massachusetts.

David graduated from Springfield H.S. in Illinois in 1960 where his yearbook described him as, "Popular and active ... always ready for a good game of tennis." As a kid, David aspired to be an architect, a dream he realized when he obtained his B.S. and Masters in Architecture from Washington University in St.Louis. It was here that he met Sharon, the love of his life, whom he married in 1965. In 1966 he enrolled in the National Guard and served 6 years in Illinois. On Christmas Day, 1969, their first child, David Keller Jr. was born. Two years later their second child, Christopher Michael was born, followed by Brandon Richard in 1976.

Throughout his full-time parenting years, he and his family lived in Illinois, Colorado and Maine. As a father, he loved to go to the mountains, with Sharon, his boys, and their dog to chop firewood, make blueberry pancakes over a campfire, and cross-country ski. It was in the mountains where he taught David Jr. to drive a stick shift in a rusted out '68 Chevy truck, and where he cussed at many a chainsaw for not cooperating. David was also an avid birder, chess player, artist and accomplished architect. He designed the family home that was built in Colorado Springs, and worked for firms throughout his career that designed schools and grocery stores. He was a Boy Scout leader for both David Jr. and Christopher's troops, as he was an accomplished Eagle Scout himself and taught his kids how to play tennis, chess and soccer.

After his kids graduated from high school and colleges in the northeast, and the world of architecture shifted from pencils to computers, David and Sharon moved to Northern California, where David opened an art gallery while he continued to design on paper. Upon retirement they moved further south eventually landing in Southern California's Laguna Woods.

David will be remembered as a devoted husband, a loving father and grandfather, a voracious reader, a creative and talented artist. David diligently studied math, history, science, the game of chess and Chinese. He loved to read, walk his dogs, go on trips with Sharon to visit kids and grandkids, and had over 20 years of sobriety. David cared deeply for this earth and his strong ethic of conservation will carry on.

David is survived by Sharon and by David Jr. and his wife Jill and their kids Grace and Caroline; Christopher and his wife Beth and their child Brody; and Brandon and his wife Erica and their kids Josephine and Zella.