Dennis Haffner, devoted husband and father, died unexpectedly on July 9, 2024. Denny, as he was known to friends and family, will be remembered for his kind and gentle spirit, his inquisitive nature, and his willingness to help, no matter the person or the circumstance. He was a man of quiet faith and selfless yet meaningful actions, a foundation of unconditional support and love for all of his family.

Born on February 18, 1938 to Roland and Emma (Hochstein) Haffner in Yankton, South Dakota, Denny spent his early years growing up on the family farm with his two younger sisters, Mary and Judy. He attended Walshtown Elementary School (a one-room schoolhouse) and Irene High School, where he set the state record for 165 low hurdles in 1956. Denny went on to attend South Dakota State University, pursued studies in engineering and physics, and sang with the South Dakota State College Statesmen. Upon graduating in 1960, Denny relocated to the Tri-Cities area where he launched his career and met his future wife, Sally (Beumeler). They were married in 1962 at St. Joseph Catholic Church in Kennewick, Washington.

Denny's engineering mind and education led him to a long technical career supporting the Hanford mission and Pacific Northwest National Laboratory where he worked until 2001. During this time, he and his wife, Sally, together raised four children, built the family's home, and ran cattle on their property in the Tri-Cities. He loved being out in nature, whether walking on their property or hiking and camping in the wilderness. Giving back was important to Denny, and he enjoyed being a prison ministry volunteer at the Walla Walla state penitentiary for over twenty years. For Denny, however, family always came first. He was always there for his kids, running beside them in track practice, playing pool left-handed just to let them win, picking them up from their myriad of after-school events, searching out the best jumps on downhill ski runs, and hauling their moving boxes as they set up new homes around the country.

After retiring from his engineering career, Denny was not one to slow down. He continued to pursue his love of skiing and the outdoors, spending summers working on the golf course and winters in the ski shop. He served on ski patrol at Spout Springs, spent week-long ski trips with close friends and family all over the US, and became a regular on local Tri-Cities ski bus trips. His curious mind and his desire to help eventually led him to the MCBONES Research Center Foundation and the Coyote Canyon Mammoth Dig Site where he volunteered regularly.

Denny was a man of enormous generosity in service of others; his peaceful yet determined spirit touched the lives of many. He was the first to show up for work, and the last to leave, always with a smile on his face and asking only, "What's next?"

Denny is survived by his wife of sixty-two years, Sally Haffner; their four children, Russ (Dorothy) Haffner; Brian (Donna) Haffner; Billy (Michelle) Haffner, and Ann Haffner; nine grandchildren, Jake, Cade, Brian Jr., Mary (Emma), Seth, Nicholas, Jillian, Iona and Callum; one great grandchild, Delilah, and another on the way. He was preceded in death by his mother, father, and two sisters.

The family requests that memorial contributions be made on Denny's behalf to MCBONES Research Center Foundation (https://www.mcbones.org), Skyline Adventures (https://skylineadventures.org, an outreach program that brings skiing and snowboarding to youth-in-need, disabled citizens, and healing veterans at Bluewood), or your local Catholic Charities.

A funeral mass will be held Saturday, July 27 at 11:00 a.m. at the Parish of the Holy Spirit in Kennewick, Washington.