When the vet breaks the terrible news to Lena Cook, she can’t believe what she’s hearing: her best friend, 9-year-old boxer Romeo, has terminal bone cancer.

“I was shocked when I found out,” Cook told TODAY.com.

“Osteosarcoma is not treatable. The only treatment is amputation, and the rest of his body isn’t strong enough,” Cook explained. “He’s not a candidate.”

Cook’s heart breaks, and her grief is contagious; the more she cries for Romeo, she says, the more Romeo grieves.

“He’d watch me cry and he’d get angry when I got angry because he’s a very sensitive dog. It took me a few days to digest it, but then I took him to the park and we started putting together a keg list,” Cook said.” .

Cook and Romeo went from enjoying a McDonald’s cheeseburger to getting a “paw meal,” completing items on Romeo’s bucket list together in their final weeks. Romeo had to go to a local bar with his dad, get a massage from a professional masseuse, go on a date with another boxer, and even meet a celebrity – rock star and cancer survivor Biff Naked, the Globe-News reported.

“She’s also a cancer survivor and she really sympathizes with him, and she’s a huge animal lover,” Cook said of Biff Naked, who beat breast cancer back in 2009.

Thanks to Cook’s father, a former fire chief, Romeo had to spend the day sitting in a fire truck.

“Romeo loves sirens,” Cook explains. “Whenever he hears a siren, he howls with excitement.”

Before Romeo died, he and Cook crossed 22 items off the special bucket list, including a fun-filled birthday party to celebrate Romeo’s ninth birthday. His last big adventure was traveling from his home in British Columbia to the United States. On March 16, however, the pain from his cancer became too much to bear. Romeo fell asleep that morning. He died peacefully at home with Lena Cook by his side.

“It was a bittersweet morning,” Cook said of the last rough morning she spent with her best friend. “I had to let Romeo go. I gave my dog a chance to experience things that he would never have the chance to experience. I loved being with him and I loved seeing him very happy.”

Even though Romeo is no longer with us, he is still encouraging other dogs and their owners to enjoy their time away from each other.

Cook said, “I’ve gotten hundreds, maybe close to a thousand messages from people saying it’s helped them.” . “Some people say, ‘My boxer has the same thing,’ or ‘My German Shepherd has lung cancer.’ Someone said, ‘It inspired us to spend our last days together with our cherished family members, on four or two legs, and to end happily ever after.'”

“Why the moping? Cook added.

Moved by Romeo’s story, Susan Davidson of Nova Scotia decided to create a list for her own dog, Winston, a 12-year-old Siberian Husky-German Shepherd who was diagnosed in April 2013 with cancer. Winston lived a short 3 months at the time of his diagnosis, but still exceeded expectations.

Now Davidson is focused on making sure Winston makes the most of his time on Earth.

It’s not quite chemotherapy,” she told Yahoo News Canada. “That’s going to be very difficult, especially at his age, and it could be quality of life.”

Today, less than a month after Romeo’s death, Riina Cooke left Romeo’s spirit on her Facebook page. There, Cooke connects with other grieving pet owners.

In a recent post, Cook wrote, “I really hope our story helps other dogs get treated like my Romeo.” . She concludes with an important message to all pet parents, “Don’t count the days, make them count.”