Amanda Seyfried Celebrates Dog Finn’s 15th Birthday with Instagram Photo Dump

Amanda Seyfried’s dog is continuing to get “older and funner.”

The Mean Girls actress marked her dog Finn‘s 15th birthday with a photo dump on Sunday, Sept. 22. “Finny’s 15 🥳,” she captioned an Instagram carousel dedicated to her four-legged friend.

Seyfried, 38, included photos of Finn in different costumes and wigs, along with selfies of herself lounging around with her Australian shepherd.

One photo showed off Finn’s fur dramatically blowing in the wind. Another image featured Finn posed next to a coffee mug with an orange bandana wrapped around his neck. Another sweet moment showed Seyfried holding Finn’s head with both her hands while at the beach.

Finn is an important fixture in Seyfried’s life. The Mank star previously touted her love for Finn at the 2022 Emmy Awards when she accepted an award for her performance in The Dropout.

After thanking the Television Academy and her agents, Seyfried expressed gratitude for her loved ones: “And last but not least, [thank you to] my family,” she said to her two kids, Nina and Thomas, whom she shares with husband Thomas Sadoski. “Hi, bubs, you gotta go to bed now, but thanks!”

“Thank you to my family, my mom, my husband, my dad and my kids, and my dog, Finn,” she concluded. “Thanks so much.”

She told PEOPLE in August 2019 that adopting Finn “changed” her life after she met him on the set of the 2006-2011 HBO show Big Love.

“As soon as he was mine, like 24 hours after I got him, I realized something about me needed him,” Seyfried said at the time. “He completely changed my life and helped me find my solitude and my independence. When you have a lifestyle like I did when I was in my early twenties, there were no constants.”

“It was just hard to know where I was going to be the next month because of my career,” Seyfried added. “That’s why I got him.”

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She also spoke about the advice she got when introducing Finn to her newborn daughter in 2017.

“You just take the hat home from the hospital, the one that they put on the baby after it’s born, and then you bring the hat home for like a day or two before the baby comes home and you just leave it by the dog and let him sniff it,” Seyfried told PEOPLE in 2018.

“It was the best we could do,” she added. “It was hard. It’s an interesting transition for everybody but it worked.”