A few months ago, Queen Elizabeth II appointed Kate Middleton Dame Grand Cross of the Royal Victorian Order, a large and very public sign of approval and appreciation for her granddaughter-in-law.
While the Royal Victorian Order has five classes, Dame Grand Cross is the highest in recognition of services to the Queen.
In the last decade, the Duchess of Cambridge's life has changed immeasurably.
Former BBC royal correspondent Jennie Bond said that Queen Elizabeth II reportedly admires the way Kate Middleton has taken to royal life.
"I think she admires the way that Catherine has adapted to the job of being a Queen-in-waiting."
Veteran royal editor Robert Jobson shared how the monarch gave a subtle signal to the world that hinted at how serious and his family were serious about Kate.
Jobson wrote, "In September 2005, I received a tantalizing telephone call from a senior Buckingham Palace insider. The source seemed quite upbeat; the news was happy."
He continued, "When I pressed the informant, a story unfolded that made me begin to appreciate just how important Kate was, and went a long way towards hinting at just how important she may yet become."
Jobson was reportedly told that Kate Middleton had a "series of private meetings with the Queen," and Prince William joined them.
At that time, they had at least two intimate dinners, and Queen Elizabeth had developed a "warm and relaxed relationship" with Kate Middleton.
Aside from that, the dinners were held at Windsor Castle, Her Majesty's favorite royal residence, and a place that she "regards as her home."
Over the next few years, Kate Middleton and Queen Elizabeth II's relationship has even deepened.
Despite reports that Her Majesty doesn't hold an intimate relationship with Kate, royal sources insist that Queen Elizabeth II holds her in high regard and admires how she juggles her royal life with a busy family.
Katie Nicholl told Vanity Fair last year, "Having awarded her granddaughter-in-law the Royal Family Order, the highest honor the monarch can bestow on a female member of the family at the end of last year.
She continued, "The Queen was reportedly thrilled with the Cambridges' tour in Pakistan, which saw Kate give her first-ever TV interview and make headlines around the world with her well-considered wardrobe choices and her unusual decision to stop the royal convoy so the couple could meet a family."
According to Richard Fitzwilliams, giving Kate Middleton the highest honor was Queen Elizabeth II's way of "acknowledging eight successful years of marriage and the fact that the Duchess has produced three heirs, thereby securing the lineage of the House of Windsor."
Kate is described by royal author Leslie Caroll to have the beauty, poise, dedication, and reliability a Queen Consort needs.
However, royal journalist Phil Dampier, told Express UK that for eight or nine years, before they got engaged or married, there was reportedly a phase where Kate Middleton appeared to be doing very little.
"The Queen once remarked Kate doesn't do very much, so I think she had a fairly long entrance to the royal family."
Despite the difficult start, Cambridge's Duchess has more than settled into her role and appears to have taken to royal life smoothly.