The couple, who are expecting their second child together, announced the happy news on Saturday. In a sweet Instagram post, Duff shows off her baby bump while receiving an embrace from Koma.
"We are growing!!! Mostly me," the Younger star, 33, 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."
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Duff and Koma, who tied the knot last year in an intimate Los Angeles ceremony, welcomed their first child together in October 28.
“Banks Violet Bair this little bit has fully stolen our hearts! She joined our world at home on Thursday afternoon and is absolute magic,” the actress wrote alongside a portrait of herself cradling her newborn.
The proud new dad also shared the exciting news, writing, “Banks Violet Bair /// 10.25.18 /// We welcome a beautiful daughter, little sister, and best friend for life. Could not possibly be more grateful for our growing family and for the 🍊 who makes it all possible. Cloud ten.”
Although Luca is the best big brother her daughter could ask for, Duff previously revealed that it took some time before he embraced the role.
“It was just he and I for so long that he was like, ‘Why? Why, Mom? Why would you do this? I really just love the way it is,’ ” Duff recalled during a conversation with PureWow back in January. “And it wasn’t bratty, it was just so sad.”
Fortunately, her son had a change of heart once his sister Banks was born.
“He came in after I had her. I was just holding her, and the look on his face was an absolute shock. He just said, ‘That’s my sister!’ And he had to sneeze, so he ran out of the room and was like, ‘I’ll be right back.’ He let out this huge sneeze in the hallway and said, ‘I had to sneeze and I knew I couldn’t do it in here near her.’ ”
"We're obsessed with our kids and [we're like], 'Should we do one more? Is this a good time?' " she said in July. "It's tough because everything is so uncertain. Like, is it safe to have a baby right now? We don't know. Can we hold on for two years or is work gonna be crazy?"
"We're always kind of talking about it and toying with the idea, but nothing too serious yet," she added.