Pregnant Ali Larter showed off her growing baby bump in a tiny pink bikini via Twitter on Monday, Aug. 18 Credit: Courtesy of Hayes MacArthur

Babymoon bliss? Pregnant Ali Larter showed off her growing baby bump while vacationing with her actor husband Hayes MacArthur on Monday, Aug. 18.

"Bumpin'," MacArthur, 37, captioned a snapshot of Larter via Twitter. The Heroes alum proudly gave a glimpse of her bare belly in a pink bikini beside both a pool and the ocean.

Larter, 38, confirmed she and the Friends with Better Lives actor were expecting their second child during an appearance on The Tonight Show With Jimmy Fallon last week. (The married couple of five years are already parents to 3-year-old son Theodore.)

"Last time you were here was three years ago and you were pregnant on the show," Fallon said at the time.

"Yeah, I came on and I was pregnant," the Legally Blonde star replied. "It went so well that I said to my husband, 'I'm going on Fallon [again]. You know what that means? Got to get pregnant!'"

She then joked about trying to conceal her baby bump while filming TNT's Legends. "I just kept telling [people] I've just been eating so many cheeseburgers."