The couple shared matching boomerangs on Instagram with their own sweet captions.
This will be Duff’s third child. She shares a 2-year-old daughter, Banks, with Koma and an 8-year-old son, Luca, with ex-husband Mike Comrie.
Koma is a singer/songwriter/producer who has worked with some of the biggest names in music, including Zedd, Tiesto, Alesso and Shania Twain.
Duff is currently in New York City filming the final season of her hit series “Younger.”