Hollywood stars Demi Moore and Bruce Willis, a couple until 2000, become grandparents.

As her eldest daughter Rumer Willis confirmed via Instagram on Tuesday, she is expecting the first child.

Her father is her partner Derek Richard Thomas, the singer of the Californian band Vista Kicks.

Two years ago, the actress ("Empire") let it be known that she had repeatedly spoken to her father about expanding the family.

The 67-year-old Willis, who has since been diagnosed with the speech disorder aphasia, has always wished that she would have a son.

The family, said the Golden Globe winner, needs more "male energy."

Indeed, as evidenced by photos on social media, Willis is surrounded entirely by women.

In addition to 60-year-old Moore, with whom he remains close friends despite a tumultuous divorce, the Die Hard actor shares his life with daughters Rumer, Tallulah and Scout, as well as his second wife Emma Heming and daughters Evelyn and Mabel .

Rumer Willis has not yet revealed the gender of her child.

She simply signed the post showing her baby bump with the emoji for a germinating plant.

Her mother Demi Moore was already delighted on Instagram: The 60-year-old shared the photos of her daughter and wrote: "I'm stepping into my hot crazy grandmother era".

Rumer Willis is also an actress in front of the camera.

She starred alongside Demi Moore in her first film, Now and Then, and in 2005 she co-directed Hostage with Bruce Willis.