Michael Kovac/Getty Hilary Duff
Sharing in a video that they were "going somewhere special," Duff asked Koma, also 33, about their destination in the clip. The singer-songwriter joked that they were going "to a farm to get murdered," before the Younger star revealed they were actually on their way to get a new dog as she covered her mouth with glee.
Then, in a separate Instagram Story, Duff shared a close-up shot of the St. Bernard puppy on the floor of her family's car as they traveled back to their home with the new furry friend. "Baby girl no name .... taking suggestions," Duff wrote with the photo.
Later on Sunday, Duff also shared a shot of her son Luca Cruz cuddling with the family's new addition, writing, "Easy like Sunday morning," alongside the sweet snap.
The new dog is the latest animal addition to the actress's family after she previously welcomed other canines into her brood over the years.
Posting to Instagram at the time, Duff captioned a shot of her and Koma standing outside with the bandana-wearing canine, "Hey guys! We adopted an old dog."
Duff adopted Lucy from the same rescue that matched her with puppy Momo back in May 2017, and she is also mom to a French bulldog Peaches.
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The new pup's arrival comes less than a month after the Lizzie McGuire star announced that she and Koma are expecting their second child together.
In a sweet Instagram post, Duff showed off her baby bump while receiving an embrace from Koma. "We are growing!!! Mostly me," she captioned the post.
"Lol quarantine was fun. Baby #3 - 2021," Koma wrote alongside the same affectionate social media share, which he playfully tagged as being taken in "Pregnantville."