"Very excited to not have to hide this anymore. Everyone I told first was like ‘uh yeah we knew thanks,' " Chrissy Teigen captioned the snap

Chrissy Teigen Shows Off Her Baby Bump After Announcing She's Pregnant Again

Chrissy Teigen is bumpin’ along!

After announcing her second pregnancy on social media Tuesday, the mom-to-be, 31, showed the first glimpse of her baby bump in a mirror selfie shared on Snapchat.

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“Very excited to not have to hide this anymore. Everyone I told first was like ‘uh yeah we knew thanks,’ ” Teigen captioned the photo of herself wearing a strapless black dress.

Teigen and husband John Legend — who celebrated their fourth wedding anniversary on Sept. 14 — are already parents to 19-month-old daughter Luna Simone.

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“Luna, what’s in here?” Teigen can be heard saying in the background of the baby announcement video, with the future big sister pointing at her mom’s stomach and proclaiming, “Baby!”

As far as Luna’s big-sister capabilities? Her Grammy- and Oscar-winning dad thinks she’ll be a great sibling.

“She is very sweet and she likes to share, so hopefully that will translate,” Legend recently told PEOPLE.

Teigen has been candid in the past about her and Legend’s journey toward conception with Luna, revealing in February 2016 that the couple chose to implant a female embryo during the in vitro fertilization round that resulted in the pregnancy with their daughter.

“The first little girl didn’t work, and then the second is Luna,” she told InStyle for their November cover story, explaining that she and Legend started with 20 embryos, but that number was narrowed down to three after screening and based on what was “going to be good for [my] body.”

The sex of the couple’s second child on the way is unconfirmed at this point, but a son wouldn’t be a surprise.