Demi Moore and Bruce Willis are expecting their first grandchild

Demi Moore Bruce Willis Rumer

Demi Moore is going to be a grandmother! The actress' daughter, Rumer Willis is expecting her first baby with her partner Derek Richard Thomas, the couple revealed in a joint Instagram post.

Moore shared the post of their announcement on her own Instagram.

"Entering my hot kooky unhinged grandma era," Moore, 60, wrote alongside photos of the pair.

For her part, Rita Wilson responded: "What happy, happy news!!!!!"

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A post shared by Demi Moore (@demimoore)

Emma Heming Willis, who is married to Ramer's father, Bruce Willis, also shared her excitement for the mum-to-be.

"Baby news is happy news!!! Congratulations @rumerwillis and @derekrichardthomas We are elated over here!," she wrote in turn on Instagram.

Rumer and Thomas made the announcement by uploading photos of the mum-to-be's bulging belly.

In the first snap, the dad-to-be wrapped his arm around her belly and gave her a sweet kiss, while Ramer smiled.

In another image she showed off her pregnancy body as she stood near a window. Another snap showed the dad-to-be very excited. The couple has been together for about a year.

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