Exclusive: Princess Eugenie reveals sweet sisterly practice with Beatrice

Princess Eugenie has recently revealed a touching insight about her sisterly bond with Princess Beatrice, exclusively telling HELLO! that she and her sister swap parenting advice.

This revelation comes just days after Princess Beatrice revealed that she and husband Edoardo Mapelli Mozzi are expecting a second child together, a sibling for Beatrice's eight-year-old step-son Wolfie, and three-year-old daughter Sienna.

Eugenie is, she admits, very much looking forward to becoming an auntie again and reveals she swaps parenting tips with Beatrice "all the time".

"I ring her a lot about meltdowns and what we do and this and that. When I was Instagramming that photo, I rang her, and I was like, 'What do you want me to say?' Because I always want to ask, just in case. And she said, 'Can't wait to talk about the trials and tribulations of motherhood'.

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'I posted about our mothering journey, because it really is like you become part of a club - a mothering club. And when your children are the same age and they're going through the same things, it's just the luckiest thing in the world… And Bea's my big sister, I talk to her about everything."

HELLO! has joined the Princess on a visit to Christie's to see Blue: Art for the Ocean, an exhibition of works by 35 artists from around the world, which will be auctioned this week to raise funds for Blue Marine Foundation.

"It's so cool," she says of the gallery, which boasts a captivating photograph by Marina Abramović entitled Performance for the Oceans, a piece in Lego by Ai Weiwei and an oil on acetate work by Peter Doig.

As well as being a dedicated mum-of-two, the Princess is also an ambassador for Blue Marine Foundation, and she shares her love of the oceans with her two sons, August, known as Augie, and Ernest, who she shares with Jack Brooksbank.

August and Ernest are not yet aware they have a new baby cousin on the way.

"I haven't got that far yet," says the Princess. "I think maybe Augie will see the tummy growing and realize but no, they don't get it. Just yet."

And she looks emotional as she shares how her mother Sarah, Duchess of York, is "so happy" about the news. "Mum's funny, because she loves her grandchildren so much but you can just see this pride for her two daughters.. she's like 'my babies!' When you become a granny you have the pride for the baby and your baby, you know? She's got a double whammy there."

Christie’s Post-War and Contemporary Art Day Sale will take place on October 10th. The Post-War and Contemporary Art Online Sale will be live October 1st - 15th.

To read the full exclusive interview, pick up the latest issue of HELLO! on sale in the UK on Monday. You can subscribe to HELLO! to get the magazine delivered free to your door every week or purchase the digital edition online via our Apple or Google apps.