Good Morning America star George Stephanopoulos and his wife, actress and comedian Ali Wentworth, are mourning a devastating family loss — one that came just days after they celebrated one of the happiest milestones of their lives: their daughter’s college graduation.

On Wednesday, May 28, Ali, 60, shared the heartbreaking news on Instagram that the family had lost their beloved dog, Cooper — a companion she described as an irreplaceable part of their home and hearts.

“I lost my longtime companion,” Ali wrote in a touching caption alongside a montage of photos. “The greatest dog and integral part of our family.”

In her emotional tribute, Ali painted a vivid portrait of Cooper’s unforgettable personality — from swimming after a giant elk in a pond, to surviving an entire bottle of melatonin without missing a beat, to stealing Christmas candy year after year.

She recalled how he slept at the foot of their bed, dreaming of running in place, loved every species — especially humans — and greeted every guest with kisses and cuddles.

“Cooper was unconditionally adored by all,” she wrote. “I will miss him with all my heart. See you on the other side, Coop. We still have many squirrels to chase…”

The post was met with an outpouring of love from Ali’s Hollywood friends and fellow celebrities.

Beth Ostrosky Stern shared a cherished memory:

“Cooper helped me rescue that gull on the beach during one of our many beach walks… the bestest boy!!!!”

Jennifer Garner simply wrote,

“A special kind of heartbreak,” followed by a broken heart emoji.

Sean Hayes added,

“Aww. I loved him. So sorry honey!”

Julianne Moore commented,

“Oh no Ali. I’m so sorry.”

Demi Moore also offered her condolences:

“Sending you all love! They are truly the most heart-expanding gift we are blessed to share our life with!”

In a second post later that day, Ali shared another montage of Cooper spending cherished moments with their family. She and George, 64, share two daughters — Elliott, 21, and Harper, 19.

Poignantly, the loss came just days after the family celebrated Elliott’s graduation from Brown University.

On Sunday, May 25, Ali proudly posted photos of her daughter’s big day, writing:

“She did it! Happy graduation to an incredible human being who has her father’s brain and my legs. And if it was the other way around — she’d be screwed. Proud parents! All our children deserve an education!”

George also marked the milestone with his own heartfelt post:

“We have a college graduate!!! Congratulations to Elliott, and to the entire class of 2025. We love you and are so proud of you, E!”

The proud father later spoke about the special moment live on Good Morning America on Monday, May 26.

“Elliott had a great weekend,” George shared. “She graduated from Brown on Sunday. She was all smiles all weekend long and we are so proud of her.”

Just two years earlier, in August 2023, Ali had already reflected on the deep emotional weight of parenthood and change when they dropped their younger daughter Harper off at college — officially becoming empty nesters.

“We dropped our baby off at college,” she wrote at the time. “Everyone is saying she’s ready to launch! But… I don’t think I’m ready!”

She described missing the everyday routines — cooking pasta, picking up wet towels, and breathing in her daughter’s familiar scent — calling the transition “brutal on the parents.”

Now, as they balance both celebration and sorrow, George and Ali’s family story stands as a powerful reminder of how quickly life can shift — from pride and joy to quiet heartbreak — sometimes in the very same week.