The Mumford & Sons frontman, 30, and his actress wife were spotted grabbing a bite to eat at London hot spot Sexy Fish Thursday night, where The Great Gatsby star may have been sporting a baby bump under her loose-fitting black top.
On Tuesday afternoon, the 32-year-old was also spotted on the set of her upcoming crime-drama miniseries Collateral, wearing a blazer with a possible baby bump peeking through.
Reps for Mulligan and Mumford are not commenting on a potential pregnancy.
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The couple are already parents to 20-month-old daughter Evelyn Grace.
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Although the pair are generally quiet about their personal lives, Mulligan has opened up in the past about her marriage and growing her family.
“Like anyone, you try and split your time evenly,” the Suffragette star told Vogue shortly before Evelyn’s birth in 2015. “Marcus is the only thing that’s mine that I can keep totally away, so I try to.”
Pal Miller told Vogue in 2015 of the philanthropic couple that there’s “an amazing balance they’ve managed to strike” on the farm where they live, away from the limelight, and that Miller “can’t wait for a little baby to come along.”