If you had asked Kate Walsh during season 1 of Grey’s Anatomy back in 2005 if she thought the show would be the massive success that it has turned into, she would have said “no way.” That said, here we are nearly a decade and a half later with the series — which recently bested ER to become the longest-running primetime medical drama — heading into season 16 with seemingly no end in sight.

Kate, for one, has her own opinion on why that is the case.

“Everybody hopes their show is successful, but no one would have ever anticipated that kind of success,” the actress, 51, exclusively told Closer Weekly while promoting her partnership with Zoetis Petcare. “That kind of run, it’s crazy! It’s amazing.”

'Grey's Anatomy' season 3 Cast
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Shonda [Rhimes] wrote great characters. There’s also a consistent setting, a hospital, and it’s always going to be drama. Even with the massive amount of content and different streaming services, there’s a beauty in the simplicity and the coziness of being able to tune in every Thursday night and see your people you’ve grown attached to over a decade — or more, in this case,” she added. “There’s a certain love, it’s like a little long-term relationship. People love those characters. I love them still. There’s a great love and connection and loyalty to them.”

As for what her iconic character, Dr. Addison Montgomery, would be up to these days or if she would ever return to Grey Sloan Memorial Hospital, Kate is quite uncertain on both.

“I don’t know. I have no idea,” the Under the Tuscan Sun star admitted. “I don’t know what she’d be up to. I feel it’s a character I played so long ago and I played her for almost a decade.”

In the years since Grey’s Anatomy — and her character’s own spinoff series, Private Practice, which ran from 2007-2013 — Kate has worn many hats. In addition to continuing to act — with roles in movies like The Perks of Being a Wallflower and Girls Trip as well as TV shows like Bad Judge, 13 Reasons Why and The Umbrella Academy — she is an entrepreneur and businesswoman with her beauty and lifestyle company Boyfriend, which she launched in 2010.

Kate Walsh on 'Grey's Anatomy' Dr. Addison Montgomery
Adam Taylor/Abc-Tv/Kobal/Shutterstock

It’s this phase in her life which she has learned the most from. While originally trying to take on all the work herself, she eventually realized that wasn’t sustainable. It became pretty clear that “it’s really about teamwork, like letting other people do their job and trusting that they know how to do it.” Even though she was still very hands-on, it was about delegating and her letting people “feel empowered.”

This is what led to the advice Kate says she would give her younger self.

“Ask for help more. Don’t try to do everything yourself,” Kate noted. “For me, that particular wisdom came with age. I’m also a real go-getter. I was an outsider a little bit which made me, I think, more compassionate for taking part in causes and fighting for the underdog. I think that made me kind of a fighter in a good way.”

It’s this mentality that has led to Kate being so outspoken about many topics that touch her heart — and why she teamed up with Zoetis Petcare. This month, she is lending her star power to help educate dog owners about skin allergies in dogs and when to visit the veterinarian to see if treatments like Apoquel can help stop their dog’s itch and bring back their A-game. Dog owners are encouraged to share photos or videos of their canine pals to social media using the #MyDogsAGame, with each post triggering a $10 donation to Zoetis Petcare’s K-9 Courage Program.

Kate Walsh and rescue dog Rosie
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Kate, who grew up having furry friends around — “we were a house that always had animals in it” — is likely why her rescue pup Rosie. “She’s unconditional love and affection and a source of joy,” Kate said about her four-legged companion. “I work on location a lot and when I can’t take her with me — you know, she’s a bigger dog — there’s just a total lack of energy in the house. She’s my family.”

Given the fact that she was raised by parents who were activists — her dad was a big union advocate and worked hard for workers’ rights, her mom was a social worker and her stepdad was a psychologist in the state prison system — Kate sees being outspoken a “combination of both” a passion and a responsibility.

“Whenever I can honestly and with integrity lend my voice and energy to causes that are important,” she notes about being of service to others, “then I’m happy to. That’s how I was raised.”

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