And on Instagram, the Mamma Mia! star shared the sweetest photo of the family's Australian-Border Collie mix, Finn, looking lovingly into the camera.
The star didn't caption her Instagram post, and fans were immediately captivated by just how adorable the pooch was.
WATCH: Amanda Seyfried's husband adorably entertains their baby son
Many fans left strings of emojis in the comments, mostly comprising of hearts and heart-eyes. "What a sweetheart," wrote one commenter, while another simply called Amanda's pet "cute."
One fan wrote: "Finn's the cutest," while another beamed: "Ear floof melts my heart!" and a third said: "What a gorgeous face. Thank you for sharing!"
Fans loved the adorable snap
The dog continued to get lavished with compliments in the comments, with another person adding: "That's the face of a good boy," and one saying: "Such a beautiful dog, lucky you!"
Although fans loved this picture of Amanda's dog, a recent snap of the pooch ended up dividing them. In the photo, Finn was sporting a plastic face shield, like the ones many people have worn during the COVID-19 pandemic.
Many fans giggled at the photo, with one noting how well-behaved Finn must have been to allow the actress to put the protective headgear on him.
However, many thought the Mank star had been cruel to her beloved pet, with one demanding: "He can't breathe; remove it!"
Amanda and her family have a close bond with the pooch
Amanda immediately defended her actions, responding: "He can breathe. And it was on for 30 seconds. It's not actually a dog shield because they can't get COVID."
Other fans chimed in to defend the actress, with one writing: "If you follow her, it's pretty obvious how much she loves that doggo. She wouldn't do anything to harm it."
Another questioned: "Do you seriously think she would put that on her dog if he couldn't breathe in it? Seriously?"
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