Happy birthday to the Princess of Wales

• Kate Middleton, Princess of Wales, celebrates her 42nd birthday tomorrow
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As she prepares to celebrate her 42nd birthday, Catherine, Princess of Wales, may take some time to reflect on how much her life has changed over the past 12 months.

It has truly been an extraordinary journey for Catherine Middleton, from an ordinary – albeit wealthy – background to royal life.

But the death of Queen Elizabeth II meant that she was asked to take another giant step forward – from the supporting cast to the title role.

Today, as Princess of Wales, Catherine is one of the four key people holding the British monarchy together, ably supported by the Duke and Duchess of Edinburgh.

It may not be easy to take on more responsibility, given the demands of a young family, but the transition into the role of queen-in-waiting has been smooth, if not seamless.

One aspect of this was her increasing confidence in one-to-one connections.

William and Kate clearly enjoy working together and the two have become a polished double act.

However, Kate is now developing her own public identity.

While in the past we may have seen her step back a bit, fitting in where it seemed right, these days Kate feels comfortable leading the conversation or playing hostess at big events.

These include, for example, the 'Together At Christmas' carol concerts at Westminster Abbey. Last year, the princess led the royal family in honoring the late queen.

But Kate also takes the lead on a range of other less important engagements, such as a visit to the Baby Bank with her children.

They had a long courtship before Kate and William announced their engagement in 2010.

But, although this position may seem privileged to most of us, life on the sidelines as a royal girlfriend was never preparation for the job in itself.

In fact, there was a time when she was criticized for her patience and was mocked as “Natty Katy,” and there was good reason to believe that her relationship with William would end only in tears.

So it was understandable that Catherine would need some time to be able to shape her own royal role – especially since there was the turmoil of Megxit and Harry's departure to America to deal with.

Earlier this year, the Princess of Wales spoke about her struggle in learning to become a royal on a visit to a youth charity.

Away from the cameras, the princess answered questions from students at St Catherine's School in Bristol about her life, telling them that she had never thought about becoming a member of the royal family until she fell in love with William.

Ms Kelly Holmes, who was present at the event, said: “She said she had to learn. It is a struggle to know that you can be accepted and fit in and that you are still learning every day.

“Public speaking isn't something that comes naturally to a lot of people, right?” She said she was still working on this but she had to plan for it. So, you know, again, I humanized everything. Not everyone is perfect.

In the end, it's clear that her efforts have paid off and the best is yet to come for Kate in her 40s.