A royal source has claimed that Carole Middleton has become a 'real Mary Poppins-like figure' to her three eldest grandchildren, as she has taken over some key roles for the Wales family amid Kate Middleton's ongoing health battle. 

A royal source has spoken to The Independent about the vital role Princess Catherine's mother is playing in her grandchildren's lives at the moment. The royal insider claimed that "Carole has been the driving force keeping the family together with minimum fuss and maximum modesty".

They explained that she has supported her grandchildren and made sure she has been available for car lifts and that someone is around to take them to their various after-school activities.

"She’s ferried and fetched George, Louis and Charlotte, taken them to school sports matches and given them endless support. She’s been a real Mary Poppins-like figure," the source continued.

It's also been claimed that the Princess of Wales's mother has embodied the 'three R’s' when it comes to her family. "She’s come to the rescue, provided reassurance, and has been a rock to Catherine and William as they come to terms with the news," the source said.

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Carole's increased support for the Wales family follows the announcement that the Princess of Wales is undergoing cancer treatment following her abdominal surgery at the start of the year.

In a poignant video released on social media last month, Catherine revealed, "In January, I underwent major abdominal surgery in London and at the time, it was thought that my condition was non-cancerous. The surgery was successful. However, tests after the operation found cancer had been present."

She added in the video, "My medical team therefore advised that I should undergo a course of preventative chemotherapy and I am now in the early stages of that treatment."

It has long been reported that Carole Middleton is 'indispensable' in helping Kate and William with parenting. Royal Journalist, Katie Nicholl, claimed on the True Royalty documentary Kate Middleton: Heir We Go Again, "One of the things that allows William and Kate to be so ordinary is the presence of the Middletons in their lives."

"Carole is a regular through those golden gates at Kensington Palace. She whizzes through in her Land Rover. There is no security because everybody knows her. She turns up to help with bedtime and bath time," said the royal expert. "She is absolutely indispensable."

Of course, the family are now located in Adelaide Cottage in Windsor, which means that the young royal family are even closer to their grandmother who is located in the same county and just a 45-minute drive from her grandchildren.