The two wed in 2010 and welcomed son Isaiah in 2015, and Underwood is currently pregnant with the couple's second child. This year, they celebrated their eighth wedding anniversary, have taken multiple trips and marked the release of Underwood's new album, giving fans a glimpse of their love on Instagram all year long.
Scroll through for some of the couple's cutest moments in 2018.
When they took a trip to Napa Valley
In May, the family took some time for a getaway to Napa Valley, California, with Underwood posting a set of photos from the trip, including one of herself and Fisher smiling in front of the region's scenery.
Along with the photo, the Oklahoma native shared a list of the group's activities that day, revealing that Isaiah even got to show off his cooking skills with chef Michael Chiarello.
"Napa Valley, you are my happy place!"" she wrote. "Amazing wine, beautiful scenery, wonderful friends, new places and a yummy dinner created by @chefchiarello and his apprentice, Isaiah Fisher! And that was just the first day here! Life is good... #napavalley #winetime #happy #IMarriedUp."
When Mike showed off his singing skills
After Underwood's single "Cry Pretty" was released earlier this year, the star shared a video she took of Fisher singing along to the track in the car, with Underwood noting in the caption, "Sounds just like the original..."
Isaiah even made a brief appearance in the clip, with the toddler heard laughing in the background at his dad's antics.
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When Underwood celebrated Canada Day
Fisher is Canadian, and his wife marked the holiday on Instagram this year with a photo of the two posing together, with Underwood wearing a hot pink dress and Fisher in a navy blue suit.
"In honor of #CanadaDay I thought I’d post a pic of me and my favoUrite Canadian...circa last night," the singer captioned the snap. "Sending lots of love to all my family and friends in the Great White North!"
When they celebrated their wedding anniversary
Underwood and Fisher got hitched on July 10, 2010 in Georgia, and the American Idol winner marked the occasion this year with a couple's selfie and a sweet caption.
"Here’s to 8 years, babe!" she wrote. "Where does the time go?! I love you today more than yesterday...which was more than the day before...and so on and so forth. Here’s to many more years together! [Love] you!"
When they attended a wedding
In July, Underwood shared a photo of herself and Fisher attending a wedding in a vineyard, with the singer wearing a red maxi dress with a colorful floral pattern.
"Wedding weekend vibes..." she wrote.
When they celebrated Carrie's album release
Underwood shared this sweet black-and-white selfie of the pair after the listening party for her new album, Cry Pretty, in August, borrowing some lyrics from fellow country star Martina McBride for her caption.
"My baby loves me just the way that I am," she wrote.
When they had a date night
The two enjoyed a date night at Etch restaurant in Nashville later that month, with Fisher posting a photo from the evening.
"Date night with my better half!!" he wrote.
Photo Credit: Instagram / @mfisher1212