The Princess of Wales's brother has shared a new photo of his two-year-old son playing with the family's golden retrievers.James, 39, took to Instagram to post an idyllic snap of Inigo playing with Mabel and Isla, the newest addition to his family, on the pooch's fourth birthday.The toddler looked adorable in a navy and white striped jumper, matching trousers and boots, as Inigo posed with the two dogs in a field full of flowers.'Happy 4th birthday, Isla,' James captioned the photo that was shared on Sunday night.Among those who wished Isla a happy birthday was Monty Don, who adopted her brother Ned from James in 2022.The gardening expert told The Sunday Times: 'I bought my puppy Ned from James Middleton. My son sent me a picture of the spitting image of one of my dogs. It turned out to be James Middleton's.'James read my book about my dog Nigel, and emailed me saying, "I was very moved by your story about Nigel. My dog is having pups. If you want to replace Nigel, I've got a nice dog that looks like him."' Ned and Isla were reunited at the Chelsea Flower Show last year, as they enjoyed the delights of a dog-friendly garden - including a lawn and water features - that Monty created. The Princess of Wales's brother has shared a new photo of his two-year-old son Inigo playing with the family's golden retrievers in a sweet update about his familyThe entrepreneur first introduced his followers to Isla, who was one of the puppies Mabel gave birth to, in October 2022, as James explained the significance of her name. At the time, he shared an image of his wife, Alizee Thevenet, cuddling Isla and their dog Mabel and captioned it: 'My Golden Girls.'He explained: 'Many of you have been asking if we kept a puppy from Mabel's recent litter and…of course we did…introducing Isla.'Her name is a little nod to her Scottish roots and [she] has already found her place in the pack.'Isla is a variation of Islay, a Scottish island on the west coast. The puppy shares her name with a member of the royal family, Isla Phillips, who is the daughter of Peter Phillips and granddaughter of Princess Anne.It comes after James revealed he joined Catherine for parts of the Three Peaks Challenge to honour the promise he made to his 'darling sister' after her cancer diagnosis in an emotional message.After a video showing James helping his sister down Mount Snowdon was posted online, the youngest Middleton sibling, 39, announced they completed a portion of the gruelling endurance event together in a post on Instagram last night.James, who runs dog food brand Ella & Co, shared a moving snap of the future Queen hugging him, taken by royal photographer Matt Porteous, with the caption: 'I'm so incredibly proud of my darling sister. In April, James posted a photo of his mother, Carole Middleton, reading to Inigo Little Inigo looked to be enjoying the outdoors by roaming around flowers and playing with the dogs. 'Two years ago, I told you we'd climb this mountain together,' he wrote. 'We talked about climbing mountains while you were in hospital, and about the incredible healing power that nature can have for both the body and the mind.'James said it was an 'honour' to join Catherine for the physical challenge, which involves scaling three of the highest peaks in the UK within 24 hours, to spread her message about life after cancer and raise funds for the Royal Marsden Cancer Charity.He praised his older sister's 'strength, resilience, and determination' to complete the Three Peaks Challenge 18 months after announcing she had completed her chemotherapy treatment and is in remission from the disease.'Your strength, resilience, and determination, all while being the most amazing mother, wife, daughter, and sister, inspire me and so many others every single day,' James wrote.'Keep being exactly who you are,' his beautiful message to Catherine read.James and his financial analyst wife, Alizee, welcomed their son Inigo on 21 September 2023. On the occasion of his second birthday, James shared a photo of Inigo with his arms wrapped tightly around the family's golden retriever, Mabel. He captioned the post: 'Happy Birthday Inigo.'We love you as much as you love Mabel….and that is a lot and Ella is saying hello today too.'Ella was James's eldest and beloved cocker spaniel, who passed away in January 2023.She was the subject of his 2024 memoir 'Meet Ella: The Dog Who Saved My Life', in which the businessman and mental health advocate opened up about his battle with depression and the role the pooch played in his recovery.In the vibrant picture, Inigo, whose face is obscured by Mabel's neck, is dressed in a pair of blue shorts, a blue polo shirt, and red, white, and navy stripy socks.The photo, snapped on a sunny day when a rainbow lit up the sky, was likely taken near the Berkshire farmhouse that James, Alizée, and Inigo share, not far from where the three Middleton children grew up with parents Carole and Michael.Since his marriage, James has occasionally posted glimpses of his and Alizée's rural life together, often surrounded by dogs, fields, and fresh air.James, who founded dog food company Ella & Co, has been open about his past struggles with depression, and has previously credited nature, animals, and fatherhood with transforming his mental health.In 2021, he took to Instagram to detail his experience, writing, 'It has been exactly 1255 days since I got diagnosed with clinical depression - but that day was the first day I learnt about mental health and how it is integral to the way we live our lives.'Earlier this year, James spoke about the 'pressure social media puts on us' after fans noticed he had been inactive on Instagram for a while. James made a social media comeback with adorable snaps of Carole reading to Inigo, as he wrote: 'We are back. 'Many of you have been asking if I am ok. I have been absent from social media for a while. The truth is, this Lent I decided to give up social media (and it was wonderful)'Sometimes we don't fully realise the pressure social media puts on us until we take a step back. If I could offer one piece of advice for 2026, it would be to try it yourself; a week, a month, or even longer…'Catherine's younger brother said that he, his wife Alizée, their baby Inigo and the dogs 'are wishing you all a very Happy Easter and thank you for checking in on me'.Ever the doting grandmother, Carole Middleton, 71, was pictured reading 'The Tale of Benjamin Bunny' to little Inigo as he was perched on her lap, on a bench, during a sunny day out.In other photos, little Inigo looked to be enjoying the outdoors by roaming around flowers and playing with the dogs.