A key part of a working royal's job is raising awareness of charities and organisations close to their hearts.
Whether it's Prince Charles and Prince William's dedication to the environment or The Countess of Wessex's plight to raise awareness for avoidable blindness in less developed countries, many royals are advocates for important causes. The Duchess of Cambridge is no different as she has become a leading voice in the field of early years development and looking after children's mental health.
In February this year, Kate took a trip to Denmark to learn more about the cause as the country is consistently named as one of the top five countries in the world to raise a family. Her visit saw her meet with Queen Margrethe and Crown Princess Mary of Denmark, as well as enjoy a number of engagements, including a trip to Stenurten Forest Kindergarten to speak about children's mental health.
Kate's work has attracted a great deal of attention and royal fans love her for it, so much so that they have come up with a sweet nickname for her.
Much in the same way that Diana, Princess of Wales was first nicknamed 'The People's Princess' in 1992, The Duchess of Cambridge has been dubbed 'The Children's Princess' by royal fans on social media.
The term has been in circulation ever since Kate's clear interests in early years development started and it has only gone from strength to strength.
Hundreds of ardent royal fans have started to use the term when talking about the Duchess on social media.
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One user wrote: " The Duchess of Cambridge is proving yet again why She is The Children's Princess. She loves working with and working for children. Catherine is wonderful and I'm excited to see the things she will do in the future."
Another added: "HRH Catherine, Duchess of Cambridge will forever be the princess of children's hearts."
One fan wrote ahead of Children's Mental Health Week: "I can't wait to see what the Duchess of Cambridge, known as a Children's Princess, has in store for us on #childrenmentalhealthweek next week."
Another person added: "I think children see her as this ethereal being, like Glinda the Good Witch or Cinderella. Someone who is almost magical. I know that's how I would see her."
The Duchess of Cambridge is highly regarded for her interests in physical wellbeing, children's development and mental health. And, as a result, she has already made a name for herself for her impressive work.
Catherine launched The Royal Foundation Centre for Early Childhood in June last year and set up the successful 'Big 5' survey which helped us to learn about the first five years of a child's life.
The Duchess has also spent the last 10 years examining how social challenges such as addiction, mental health and homelessness affect someone as they grow up.
In May, it was revealed that Kate had been made the new patron of the Maternal Mental Health Alliance (MMHA) charity. The Duchess appeared in a promotional video where she spoke about how no mother is "immune to experiencing anxiety and depression".
She said: "But we all know that pregnancy, childbirth and the first months and years of a child's life can be hugely demanding. Parents often feel lonely and overwhelmed by these early years.
"Around 20 per cent of women in the UK are reported to experience perinatal mental illness. Sadly, we also know that many more are suffering in silence.
"No one is immune to experiencing anxiety and depression during this time. It is crucial, therefore, that all those who might be struggling are given the right support at the right time, so that they're able to share these feelings without fear of judgment and can access the information, care and support they need to recover."