The Americans’ spies Keri Russell and Matthew Rhys have a secret: They’re expecting a baby together, a source reveals in the new issue of Us Weekly.

“Keri is more than four months along,” says an insider close to the pregnant-again mom of son River, 8, and daughter Willa, 4, with ex-husband Shane Deary, who she divorced in 2013 after seven years of marriage. A rep for Russell could not be reached for comment. Adds a source close to Rhys, “It’s so exciting for them!”

The Felicity alum, 39, and the Welsh actor, 41, deflected questions about their relationship for months after hooking up on set, but finally appeared as a couple at NYC’s Public Theater in April 2014.

Now filming the Cold War drama’s fourth season for FX, “they are always together and love roaming around New York,” a second source reveals. “Matthew is really in love. They feel they should have always been together.”

Rhys’ rep did not respond to repeated requests for comment.

On screen, the duo’s love is more temperamental. “It’s not this big, sweeping romantic movie where you have to be so in love and so beautiful and so sexy,” Russell admitted in January 2014. “You’re usually using the sexuality, at least in the spy end of it, to get something,” she continued. “So there is kind of a freedom in that, because it’s kind of messier or more direct than that.”