Keith Richards is set to become a great-grandfather for the first time

Ella, 29, shared the news on Instagram by posting a black-and-white photograph in which she cradled her baby bump.

The child will make Keith a first-time great-grandfather.

Ella is the daughter of Lucie de la Falaise and Marlon Richards, Keith's son from his long relationship with the late model and actor Anita Pallenberg, who died aged 75.

Ella has been in a relationship with photographer Sascha von Bismarck for several years, with the pair publicly confirming their romance in early 2023.

Ella spoke about her relationship with Sascha during an interview connected to a Tatler cover shoot, for which Sascha photographed her.

She said: "It was really easy. I feel very comfortable with him taking my photo, which is a very personal thing."

The announcement of her pregnancy prompted congratulations from several figures in fashion and film, including model Stella Maxwell, model Jade Parfitt and Poppy Delevingne, who responded to the post on social media.

Keith's bandmate Sir Mick Jagger, 82, is currently the only other member of The Rolling Stones to have become a great-grandfather.

Mick reached that milestone in 2014 when his granddaughter Assisi Jackson welcomed her first child.

Assisi is the daughter of jewellery designer Jade Jagger.

Sascha comes from an aristocratic German family and is the younger brother of photographer Count Nikolai von Bismarck, who previously had a relationship with model Kate Moss.

Their father is businessman Count Leopold von Bismarck-Schönhausen and their mother is fashion designer Countess Debonnaire von Bismarck, a long-time figure in London's fashion circles and a friend of Kate.

Nikolai and Sascha are also great-great-grandsons of Otto von Bismarck, the 19th-century German statesman and former chancellor who played a central role in the unification of Germany.

Ella first gained attention in the fashion world at the age of 18, making her debut at New York Fashion Week and appearing in a Burberry campaign photographed by Mario Testino, alongside Kate Moss, Naomi Campbell, Cara Delevingne and Jourdan Dunn, 35.

She later signed with the Kate Moss Agency and has since walked for brands including Prada, Calvin Klein, Fendi, Valentino and Sonia Rykiel.

Ella has also spoken publicly about her grandfather's personality, offering a portrait that contrasts with his rock-and-roll reputation.

She said: "He is very quiet and sweet and loving. He's a lot more shy than people think."

Reflecting on her upbringing within the Richards family, Ella said: "My grandfather used to wear my grandmother's clothes, and she used to wear his. Most of my family are slightly mad and crazy or weird. My whole family are all crazy creatives. No one is academic. Everyone is wild and free-spirited."