"Guess what guys! @matthewkoma and I made a little princess of our own and we couldn’t be more excited!!!!!!" Duff wrote alongside a photo of the couple. She wore a long fitted dress, giving a peek of the tiny beginnings of her baby bump.
The musician shared the same photo on his social media, and took the opportunity to compliment his glowing girlfriend. "We made a baby girl! She will be as beautiful and sweet as her mother..." Koma wrote.
The couple worked together on Duff's 2015 album, Breathe In. Breathe Out., but weren't public about any romantic relationship until January 2017. They took two breaks over the course of their time together but fully reignited their flame in December, and the rest is history. As the Younger actress said on The Talk in December, "Third time's a charm!"
Duff is already mother to her 6-year-old son, Luca, whom she shares with ex-husband Mike Comrie.