Why the Duchess of Cambridge kept two royal engagements secret yesterday

As wife of the future King, it's hard to deny that much of the Duchess of Cambridge's life is lived in the public eye.

The mum-of-three has shared all of her births with the world, appearing on the steps of the Lindo Wing just hours after welcoming her three children. We were given a front row seat on Catherine's wedding day and she regularly shares her daily royal engagements with the public.

But on Tuesday, the Duchess and her team opted to keep two unannounced engagements private from the rest of the world.

MORE:Princess Eugenie shares adorable throwback photo of her and Princess Beatrice

Catherine had a busy day of important events yesterday, spending her day visiting Sayers Croft Wildlife Garden and Forest School in Paddington, likely as part of her work with early years, and her interest in how nature can benefit young people.

Then, that same evening, she held a reception at her Kensington Palace home, for members of her Early Years Steering Group.

While normally, the palace would announce and publicise such engagements, these two were kept quiet, only announced hours after they had finished.

And although it's not been confirmed why the events were kept secret, it's likely that the Duchess simply wanted to carry out her important work yesterday without announcing it to the world.

In fact, while many royal engagements are made public, many aren't as well. The family regularly carry on their work behind-the-scenes without anyone knowing, to learn more about the causes close to their hearts.

And often, the media are not invited to engagements, as it's not considered to be vital to publicise the event, if the royal in question is simply working.

Catherine isn't the only member of the family who often heads out on secret royal duties. It's thought that the Duchess of Sussex and Duchess of Cornwall too regularly make charity visits without any sort of announcement.

Today however the Duchess of Cambridge is visiting the Anna Freud Centre on a public engagement, to open a new centre of excellence.

Arriving this morning, Catherine opted for a stylish green Emilia Wickstead dress and a pair of her signature nude heels.