The royal family rushed toQueen Elizabeth’s bedside Thursday after Buckingham Palace announced her doctors were “concerned” for her health, but a key player was missing.

The Queen’s granddaughter-in-lawKate Middletondid not join her husbandPrince Williamfor the journey north to the Balmoral Castle, the Queen’s summer retreat in the Scotland. That’s likely because it is thefirst day of schoolfor the couple’s three children,Prince George, 9,Princess Charlotte, 7, andPrince Louis, 4. The start of the new term is especially momentous for the young royals as they enroll as first-time pupils atLambrook Schoolfollowing the family’s move from London to Windsor at the end of the summer.

Kate Middleton and Queen Elizabeth.Anwar Hussein/WireImage

NOTTINGHAM - JUNE 13: Queen Elizabeth ll and Catherine, Duchess of Cambridge visit Vernon Park during a Diamond Jubilee visit to Nottingham on June 13, 2012 in Nottingham, England. (Photo by Anwar Hussein/WireImage)

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Hands-on mom Kate likely stayed behind atAdelaide Cottagefor the children’s first day of classes. However, Kate and the Queen spentquality time togetherjust weeks ago, when the Duke and Duchess of Cambridge visited the 96-year-old monarch at Balmoral with their kids, a royal summer tradition.

Queen Elizabeth II and Catherine, Duchess of Cambridge attend the annual Remembrance Sunday service at The Cenotaph on November 10, 2019 in London, England. The armistice ending the First World War between the Allies and Germany was signed at Compiegne, France on eleventh hour of the eleventh day of the eleventh month - 11am on the 11th November 1918.

Though Kate will likely be known as Queen Consort when her husband takes the throne one day, it’s unlikely thatQueen Elizabethhas ever formally tutored her, as she is not one to hand down explicit “lessons,” insiders say. Instead, historian Sarah Gristwood tells PEOPLE that the Queen may have approached her relationship with Kate the way she does with prime ministers.

Prince William, Kate Middleton, Prince George, Princess Charlotte and Prince Louis joined Queen Elizabeth and Prince Charles on the Buckingham Palace balcony on June 5.Samir Hussein/WireImage

Royal Family

“The Queen has always preferred to do rather than to say,” says the author ofElizabeth: Queen and Crown. “With her audiences with her prime ministers, if there has been actual advice, it would be a discreet ‘I think that went rather well’ rather than actual instruction.”

In an intimate sign of their close relationship, Kate regularly wears jewels on loan from the monarch and has followed her lead of wearing bright colors to be found in the crowd.

When the Queen’s historic reign was celebrated this summer at thePlatinum Jubileeweekend, the Duchess of Cambridge acted as envoy inWales, rode in thefirst carriageof the prominent procession for Trooping the Color and joined the monarchon the balconyof Buckingham Palace as the festivities wrapped.

Prince Williamand Kate, both 40, “are representing the Queen impeccably,” biographer Sally Bedell Smith previously told PEOPLE. “They’re showing a kind of dedication she would be proud of. And that probably gives her hope.”

source: people.com