\"Saying hello to the little nibblet!!\" Moore wrote in the caption. \"It's an honor to witness your journey into motherhood, and can't wait to welcome this baby in to the world!\"

Rumer Willis, 34, announced the news of her pregnancy Tuesday on Instagram, with a sweet photo of her baby bump. This will be her first baby with her boyfriend, musician Derek Richard Thomas.

Demi Moore and Bruce Willis are soon-to-be grandparents.

View this post on Instagram

A post shared by Rumer Glenn Willis (@rumerwillis)

Rumer Willis' baby will also be her parents, Moore and Bruce Willis' first grandchild.

Moore shared her daughter's photos yesterday on Instagram and wrote in the caption, \"Entering my hot kooky unhinged grandma era.\"

\"PHOTO:
Amanda Edwards/Getty Images
PHOTO: Actress Rumer Willis attends the opening night of "Love Actually Live" December 1, 2021, in Beverly Hills, Calif.
>

Moore and Bruce Willis have three children together: Rumer Willis, Tallulah Willis and Scott LaRue Willis. Bruce Willis also has two daughters with his wife, Emma Heming Willis: 8-year-old Evelyn Penn and 10-year-old Mabel Ray.

Last week, Moore shared photos of their blended family celebrating the holidays together.

In November, Rumer Willis made her relationship with Thomas official by sharing photos of the both of them during a fall photoshoot.

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