Diane Seay McNulty

Diane Louise Seay McNulty, PhD

April 1, 1949 – July 29, 2025

Diane Louise Seay McNulty, PhD, age 76, passed away peacefully on July 29, 2025. She was born on April 1, 1949, in Dallas, Texas, to Nancy Louise Weakley and Dr. Frank Oliver Seay. Diane was brave, brilliant, glamorous, and compassionate—deeply loved by her husband, children, family, friends, colleagues, and students. Her smile was infectious, her laugh contagious, her spirit unbreakable—and she always had a twinkle in her eye.

She is survived by her devoted husband of more than 40 years, Michael Sinclair McNulty, and her four beloved children: daughter Brynn Bagot Allday; son Patrick James McNulty; son Timothy Edward McNulty and his wife, Dr. Linda Elkins; and daughter Kate McNulty White and her husband, Dr. Nathan Scott White. Diane was lovingly known as “DD” by her eight grandchildren: Avery Seay Allday, Angus Stuart Allday, Aidan Sawyer Allday, Elias Patrick McNulty, Carolyn Ross McNulty, Marian Lucille McNulty, Bradley Lawrence White, and Ainsley Scott White.

She is also survived by her brother, Frank Michael Seay; her sister, Sally Seay Kreimborg and her husband, Bob Kreimborg; her sister-in-law Maggie Goodrich and her husband, Rev. Paul Goodrich; and numerous cousins, extended family, and lifelong friends.

The daughter of a U.S. Navy flight surgeon, Diane spent her early childhood in Pensacola and Jacksonville, Florida, before returning to Dallas. She graduated with honors from Hillcrest High School and went on to earn a BBA in Marketing with a minor in Journalism from Southern Methodist University, where she was a member of Beta Gamma Sigma Honor Society and the Pi Beta Phi sorority. She later earned both a Master’s degree in Management Science (Behavioral Management) and a PhD in Business Policy and Strategy from The University of Texas at Dallas.

Diane’s beauty was undeniable—a former model for Neiman Marcus’ Teen Board and SMU—but it was her strength and perseverance that truly defined her. Born with a congenital heart defect, her parents were told she would not live past the age of five. But she defied all odds, undergoing numerous complex open-heart surgeries performed by pioneering thoracic surgeons. Diane became a living example of the progress in cardiac care and surgical innovation. Her family is profoundly grateful for the many additional years made possible by her courage and the exceptional care she received.

Professionally, Diane left a lasting legacy at the University of Texas at Dallas Naveen Jindal School of Management, where she served as Associate Dean for External and Corporate Relations and Communications. She played a pivotal role in advancing the school’s mission through leadership in corporate alliances, alumni engagement, and community relations. Her work built strong and lasting partnerships and touched the lives of countless students, alumni, faculty members, and business collaborators.

Throughout her career and life, Diane was honored with numerous awards, including:

● Sandi Haddock Community Impact Award from the American Heart Association

● Outstanding Leadership in Education Award from the US India Chamber of Commerce DFW

● 2017 Women in Leadership Award from the Dallas Business Journal

● Multiple honors for MANAGEMENT magazine from MarCom and the Dallas Press Club’s Katie Awards

Diane also served on numerous national and local boards and committees including: The Public Affairs Council in Washington, D.C.; the Texas Business Hall of Fame; Executive Women of Texas; and the American Heart Association Dallas Division’s (AHA) Côtes du Coeur, where she proudly served as vice chair for two years. She was also co-founder of the Women’s Heart Guild, establishing successful fundraisers benefiting AHA, as well as a Junior League of Dallas Sustainer.

Despite facing lifelong medical challenges, Diane maintained a strong passion for travel, exploring the world with family, friends, and through the EMBA program at UTD. Her journeys took her to over 30 countries – including Switzerland, Chile, China, Finland, Sweden, India and Greece – many of which she visited more than once.

The family would like to thank the exceptional physicians and staff at UT Southwestern for their years of extraordinary care and compassion. Special thanks to Dr. Steves Ring, Dr. Beth Brickner, Dr. Michael Jesson, Dr. Jose Joglar, and Dr. Weiyi Tan, among many others. The family also recognizes and thanks Dr. Jack Schwade (Medical City Dallas), Dr. John Kirklin (Mayo Clinic and University of Alabama Birmingham), Dr. Gladys Fashena (Children’s Medical Center Dallas), and Dr. Helen Taussig (Johns Hopkins), each of whom played a part in Diane’s lifelong journey with cardiac care.

A celebration of Diane’s life will be held on Thursday, August 21, 2025, at 1:00 p.m. in the sanctuary of Highland Park United Methodist Church.

In lieu of flowers, the family invites memorial contributions to be made to: The Dr. Diane McNulty Scholarship for the Young Scholars Program at the UT Dallas Jindal School of Management - giving.utdallas.edu/mcnulty. (Please note “Dr. Diane McNulty Scholarship” in comments section) or to American Heart Association - Dallas Division by phone (800) 242-8721, online American Heart or by mail.