Pregnant Rumer Willis Poses with Sister Tallulah Willis in Sweet Photo Showing Off Baby Bump

Rumer Willis is enjoying her pregnancy with those closest to her.

The What Lies Ahead actress, 34, has been sharing the well wishes coming her way since revealing she and boyfriend Derek Richard Thomas are expecting their first baby.

In a photo shared on her Instagram Story Wednesday, Rumer poses in the mirror, lifting her shirt to show off her baby bump as she laughs. Next to her, sister Tallulah, 28, squats and playfully sticks her tongue out as she takes the black-and-white photo.

Willis and Thomas first shared their pregnancy news on Tuesday with a carousel of bump photos in a joint Instagram post.

Tallulah shared her sister's pregnancy announcement on her own Instagram the day prior, celebrating the exciting news.

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Rumer Willis/instagram

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"Entering my hot kooky unhinged auntie era 🌱," she captioned a photo where Thomas kisses Rumer's bump.

The caption echoed proud grandmother Demi Moore's post, in which she wrote she was excited to be, "Entering my hot kooky unhinged grandma era."

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Not far behind was Scout Willis, 31, who reposted the couple's photos and wrote, "🌱Activating hot, kooky, unhinged Aunt Scout era 🌱 Thank you @rumerwillis and @derekrichardthomas for co-creating my new best friend."

VALERIE MACON/AFP via Getty

The sister's also shared their excitement in the comments of Rumer's announcement post on Tuesday, with Scout joking, "I'm weep. I feel so good, What a joyful hard launch party," to which the mom-to-be replied, "all for you scouter."

Demi Moore/Instagram

"EEEEEEEE!!!!! we stan this mommy!!" Tallulah wrote.

On Wednesday, Moore shared a photo from an ultrasound appointment for Rumer, where she posed with Tallulah's dog Pilaf and the rest of her daughters in a fun family photo.

"Saying hello to the little nibblet!! Overjoyed for you, my sweet Rumer," wrote the G.I. Jane actress. "It's an honor to witness your journey into motherhood, and can't wait to welcome this baby into the world!"

The photo shows Rumer lying down for the exam with her baby bump exposed as Scout poses with arms raised and holding up peace signs on one side of Moore. On the other, Tallulah leans forward, reaching a hand over to touch Rumer's bump.