Joan Ellen Heinlen was born in Racine, Wisconsin, on November 22, 1939, to Floyd Otto Lehman and Wilma Evelyn Diane Bemis Lehman.

She left her studies at Iowa State University to marry Walter David Heinlen, Sr. on November 8, 1958. They were married in Des Moines, Iowa, but soon moved to San Mateo, California, to remain close to Joan's parents. Joan and David relocated several times while raising their family before ultimately settling in the Tulsa metropolitan area, where they lived for several decades.

Joan did not make her way to Oklahoma City until 2015. In 2018, she moved to Epworth Senior Retirement Villa, where she spent her final years.

Joan was a devoted homemaker and mother for many years. In 1990, she unexpectedly became a single mother. After facing the challenges that followed, she not only succeeded in that role but also flourished as the matriarch of her family.

She returned to college and earned a Bachelor of Science in Nursing from the University of Tulsa. Graduating summa cum laude on May 7, 1994, she began her nursing career in the Cardiovascular Intensive Care Unit at Hillcrest Medical Center. She later accepted a second position as a supervisor at the City of Faith Medical Complex.

Joan retired at the age of 65 and devoted her time to helping care for her grandchildren and traveling to visit her children. As much as she loved being a nurse, her greatest pride and joy were her children and grandchildren. She poured herself into their lives, helping them become successful, responsible, and respectable adults.

In 2019, Joan married C. Eugene McDaniel, who provided her with the companionship she had long longed for. Joan passed away on June 30, 2026. She will be deeply missed.

Joan was preceded in death by her first husband, Walter David Heinlen, Sr., and her son, Walter David Heinlen, Jr.

She is survived by her husband, Colonel C. Eugene McDaniel, USMC (Ret.), of Oklahoma City, Oklahoma;

The children of her late son, Walter David Heinlen, Jr.: Meagan Amanda Wall of Cypress, Texas, and her husband, Brian Wall. Together, they have two children, Ethan "Dax" and Vanessa. Daniel Keith Heinlen of Broken Arrow, Oklahoma, and his daughter, Royce.

Her son, William Derek Heinlen of Indialantic, Florida, and his wife, Lorie Christine Bebernes. Together, they have three children: Lindsey Christine McCart of Satellite Beach, Florida, and her husband, Rylan McCart. They have three children: Jolie, Crew, and Hope. Andrew Derek Heinlen of Stuart, Florida. Garrett Edmond Heinlen of Winter Springs, Florida, and his wife, Claire Wnuk. They have one son, Grayson.

Her daughter, Heidi Kristin Heinlen of Rockwall, Texas. Heidi has two daughters: Rachel Corinne Fischer of Rockwall, Texas, and her wife, Kelsea June Rey. They have two sons, Scott and Lincoln. Kirsten Rebecca Fischer of Hana, Maui, Hawaii.

Her son, Jonathan Edward Heinlen of Oklahoma City, Oklahoma, and his wife, Latisha Camp. They have three daughters: Elizabeth, Kate, and Scarlett.

Her daughter, Holly Kathleen Case of Edmond, Oklahoma, and her husband, Matthew Case. Together they have two children, Cailyn and Channing.