Hugh Michael O’Brien IV
31 July 1969 · 3 August 2026
Hugh Michael O’Brien IV (“Mike”), 57, of San Diego, California, passed away on August 3, 2026, at UC San Diego Jacobs Medical Center, surrounded by his family, after a three-and-a-half-year fight with stage 4 pancreatic cancer.
Mike was born on July 31, 1969, in Subic Bay, Philippines, to Hugh Michael O’Brien III and Julie Apelo O’Brien. After graduating from George Dewey High School, he attended San Diego State University and received a Bachelor of Science in Computer Science. He spent thirty years as a software engineer, most of them with defense contractors, including more than twenty years at L3Harris.
He met Maribelle in college in 1989. They married in 1993 and received the sacrament of holy matrimony in the Catholic Church in 1998. They built their family and home in San Diego and worshipped at St. Anne Catholic Church, where Mike loved the Traditional Latin Mass. He was a devoted husband, father, and brother. He loved figuring out how things worked and making them better, and he loved the outdoors, camping, and the open road. A man of deep faith, he met his illness with grace, humor, and courage.
He is survived by his wife, Maribelle B. O’Brien, and their children, Mikey (Ashley), Marisa (Noah), and Maria.
He is also survived by his father, Hugh Michael O’Brien III; his mother, Julie Apelo O’Brien; his stepmother, Nora O’Brien; and his siblings, Tara, Tim, Sammi Jo, and Kimberly.
Services
Viewing — Wednesday, September 2, 2026, 4:00 to 8:00 p.m. El Camino Memorial, 5600 Carroll Canyon Road, San Diego, CA 92121.
Funeral Mass — Thursday, September 3, 2026, 10:30 a.m. Traditional Requiem High Mass at St. Anne Catholic Church, 2337 Irving Avenue, San Diego, CA 92113.
Burial — to follow El Camino Memorial, 5600 Carroll Canyon Road, San Diego, CA 92121.
Memorials
In lieu of flowers, donations may be made to the Pancreatic Cancer Action Network (PanCAN) or to UC San Diego, in his memory.
Condolences may be shared at dignitymemorial.com/obituaries/san-diego-ca/hugh-michael-obrien-12994587.
Eulogies
In memoriam
Good evening, everyone. Thank you for being here today to remember my dad.
He was a husband, friend, brother, and son. To me, he was simply Dad—and I’d like to share what that meant.
Dad lives on in me in more ways than he may have realized. We share the same name. He inspired me to follow in his path as a software engineer. And I inherited his inquisitive mind—his refusal to take things at face value, and his constant urge to dig deeper.
That curiosity meant we could debate anything. Sometimes those conversations got a little heated—to Mom’s dismay—but they were never about “winning.” They were about testing ideas, pushing each other, and learning. I’m going to miss those debates more than I can say.
One of the great joys we shared was our love for tech—always improving, always tinkering, always trying to make the thing just a little better. We compared projects and upgrades, shared opinions about the latest gadgets, and—more than once—drove our wives a little crazy with our new toys.
Since he’s been gone, I’ve caught myself reaching for my phone to text him about some new thing I learned or a new product that came out. And every time, I’m reminded there’s a conversation I still want to have.
Dad also had a very particular sense of humor: dark, dry, and perfectly timed. Even when things were difficult, he found a way to lighten the room. In a strange way, I’ve found myself smiling the most when I think about his last hospital stay.
The situation was serious, but he brought jokes and joy into a place that can feel heavy and sterile. From enjoying that fifth-floor view, to trying clam chowder for the first time—he wasn’t the biggest seafood fan—to finding happiness in small new experiences, he kept showing us how to meet each day with grace.
One morning, after moving into yet another room, the X-ray technician recognized him. Dad met him with a big smile and let him know it was indeed him—and that this was his fifth room. Not complaining. Just amused, accepting it for what it was, and hoping that he wouldn’t have to move again. After they finished the procedure, he shared with me how cool it was that the X-ray machines were so small now.
Most people wouldn’t want to reflect on a hospital stay, but those are the moments I keep coming back to: the way he greeted nurses with a big smile, introducing us when someone was new, and even when discharge day got postponed, somehow found the positive.
Throughout the hospital stay, at the darkest moment, he remained who he was: courageous, kind, patient, inquisitive, goofy, loving—putting his trust in God’s will.
It hurts to think about how much I’ll miss him as I reach my own milestones in life. But it also brings me comfort to know how much of him I carry forward. His grandchildren won’t get to meet him in person, but they will get to meet him through me—in the stories I tell, the habits I’ve picked up, and the way I try to move through the world.
If Dad were still here, he’d probably be sharing some borderline-inappropriate joke right about now—just to make sure we’re not taking ourselves too seriously.
I’d like to switch gears a bit here and say a few words about Mom and Dad’s marriage. Like all marriages, there were moments when things were heavy and complicated. Mom didn’t give up on Dad, and Dad didn’t give up on her — for better, for worse, for richer, for poorer, in sickness and in health. During those times, he supported Mom through nursing school. He loved to cook; there was almost always a home-cooked dinner on the table. Acts of service was his love language, and he lived it to the fullest.
I’m honored to have watched their marriage grow and blossom through the years—how they grew as parents raising Marisa and Maria. And when they became empty nesters, I always looked forward to hearing about their latest adventures: where they went, what they did, and what kind of shenanigans Dad got them into.
Thank you, Mom, for being there for him with so much love, and for all the years they shared together.
And thank you all for being here today.
He whom we love is not hidden in the ground; he is received into heaven. Let us wait a little while, and we shall be once more with him. The time of our separation is not long, for in this life we are all like travelers on a journey, hastening on to the same shelter.
St. Basil the Great
Mikey