Celebrity Parents Pregnant Rumer Willis Has Baby Bump Cradled by Sisters Scout and Tallulah: '4 Best Friends' On Thursday, the mom-to-be displayed her bump in a sweet photo posted by sister Scout, which featured the three siblings By Marisa Sullivan Marisa Sullivan Instagram Twitter Digital News Writer People Editorial Guidelines Published on March 3, 2023 10:46 AM Share Tweet Pin Email Scout, Rumer and Tallulah Willis. Photo: Rumer Willis/Instagram Rumer Willis has a sisterhood of support, literally, while expecting her first baby. On Thursday, the mom-to-be, 34, had her bump on display in a cute photo posted by sisters Scout Willis and Tallulah Willis on Instagram. In the snap, Rumer stood in the middle of Scout, 31, and their younger sister, 29. "4 Best friends," Scout wrote, acknowledging Rumer's belly, which Tallulah cradled as Scout held a guitar on the other side of her expectant sister, wearing a "Nepo Baby" T-shirt. "Me and my 3 best buddies," Scout added in her own caption alongside the same photo. "That's happy ❤️," wrote stepmom Emma Heming Willis, who married Rumer, Scout and Tallulah's father Bruce Willis in 2009. The couple has two children together: Evelyn Penn, 8, and Mabel Ray, 10. The What Lies Ahead actress and her musician/producer beau Derek Richard Thomas announced the pregnancy in December 2022. The baby on the way will be the first grandchild for exes Bruce, 67, and Demi Moore, who are Rumer, Scout and Tallulah's parents. Never miss a story — sign up for PEOPLE's free daily newsletter to stay up-to-date on the best of what PEOPLE has to offer, from juicy celebrity news to compelling human interest stories. Rumer Willis Is Pregnant! Actress Expecting Her First Baby with Boyfriend Derek Richard Thomas Celebrating the joyous news, Scout did not hold back how excited she is to become a proud aunt. "Activating hot, kooky, unhinged Aunt Scout era 🌱," she wrote on a post in December, with a black-and-white shot of Rumer and boyfriend Thomas sweetly smooching her belly. "Thank you @rumerwillis and @derekrichardthomas for co-creating my new best friend," Scout added. In another black-and-white photo, Rumer showed a silhouette of her figure, with a beautiful white winter wonderland displayed through the floor-to-ceiling windows behind her. Bruce Willis' 5 Daughters: Everything to Know The Willis/Moore family is known for being a tight-knit clan, especially as they support one another through Bruce's recently disclosed frontotemporal-dementia diagnosis. The family first announced last March that he was "stepping away" from his decades-spanning acting career following his diagnosis with aphasia, a language disorder that is "impacting his cognitive abilities." "This is a really challenging time for our family and we are so appreciative of your continued love, compassion and support," they said at the time. The family added, "We are moving through this as a strong family unit, and wanted to bring his fans in because we know how much he means to you, as you do to him. As Bruce always says, 'Live it up' and together we plan to do just that."