Kate Middleton and Prince William’s inner circle just got smaller.

Natasha Archer, a trusted staffer of the Prince and Princess of Wales, is unexpectedly leaving after over 15 years of collaboration, as reported by People.

Archer reportedly made the decision to leave Kensington Palace to set up her own private consultancy.

The outlet reported that the Waleses’ household gave Archer their well wishes ahead of her new business venture.

Page Six reached out to Kensington Palace for comment but did not immediately hear back.

Archer began her tenure in 2010 as a personal assistant to the royal couple, both 43.

Throughout the years, she grew close to Middleton and became her unofficial stylist.

In 2014, Vanity Fair spoke to an insider about how Archer helped Middleton come out of her style shell.

“Initially, Kate was a reluctant fashion icon, but now she enjoys it. Tash helps source some of the clothes,” the source told the outlet.

As per a source quoted in the Daily Mail, “She shops extensively online for Kate and orders numerous dresses for her to experiment with. Natasha has encouraged Kate to be more adventurous with her style, leading to shorter hemlines and bolder fashion choices.”

Last summer, Middleton promoted Archer to be her and William’s senior private executive assistant.

The source added, “Natasha has consistently shown discretion and loyalty towards Kate, making her worthy of this recognition. The salary increase is also a well-deserved bonus.”

“This appointment means we can expect to see Natasha by Kate’s side for years to come.”

The insider added, “It seems to be Kate’s way of thanking her for her loyalty.”

Before joining William and Middleton, Archer worked in the private office of the Duke and Duchess of Gloucester.

Archer is married to Getty royal photographer Chris Jackson, with whom she shares two children.