Princess Charlotte, Prince William, Prince George

BEN STANSALL/AFP/Getty Images

Princess Charlotte is a big sister!

Prince William and Kate Middleton welcomed third child together, a baby boy, on Monday morning. Shortly after baby's arrival was announced, Charlotte and Prince George were photographed holding hands with dad William as they arrived to the hospital to meet their new brother.

The birth of the couple's third child comes almost exactly three years after the Duke and Duchess of Cambridge welcomed Charlotte into the world in May 2015.

So to celebrate Charlotte's upcoming birthday and her new role as a big sister, let's take a trip down memory lane and look back at her adorable baby album!

Princess Charlotte

Courtesy of the Duchess of Cambridge

A day ahead of her second birthday, this portrait of the youngster is released, taken by mom Duchess of Cambridge Kate Middleton at their Norfolk home, Anmer Hall.

Princess Charlotte, Official Photo

HRH The Duchess of Cambridge

The princess is seen in a photo taken by mom Kate Middleton and released a day before her first birthday.

Princess Charlotte, Official Photo

HRH The Duchess of Cambridge

The princess is all grown up!

Princess Charlotte, Official Photo

HRH The Duchess of Cambridge

Look, Mum, I can stand up!

Princess Charlotte, Official Photo

HRH The Duchess of Cambridge

What a cutie!

Kate Middleton, Prince William, Prince George, Princess Charlotte

JOHN STILLWELL/AFP/Getty Images

Little Charlotte looks absolutely precious, smiling from ear to ear as she posed in the snow with her daddy.

Kate Middleton, Prince William, Prince George, Princess Charlotte

JOHN STILLWELL/AFP/Getty Images

Decked out in pink, the little snow angel smiles as snowflakes fall around her.

Kate Middleton, Prince William, Prince George, Princess Charlotte

JOHN STILLWELL/AFP/Getty Images

The princess joined her adorably family-of-four for the very first time in the snow!

Kate Middleton, Prince William, Prince George, Princess Charlotte, Christmas Card, 2015

Chris Jelf /Kensington Palace via Getty Images

The royals posed in October for a holiday card. Kensington Palace said the Duke and Duchess of Cambridge "are hugely appreciative of all the warm messages they have received about their family this year and are very much looking forward to their first Christmas as a family of four."

Princess Charlotte

Press Association via AP Images/HRH The Duchess of Cambridge

The princess appears at six months old in a photo taken by her mother, Kate Middleton.

Princess Charlotte

Press Association via AP Images/HRH The Duchess of Cambridge

The princess appears at six months old in another photo taken by her mother, Kate Middleton.

 Catherine, Duchess of Cambridge, Princess Charlotte, Christening

Chris Jackson - WPA Pool/Getty Images

The baby appears with her mother at her royal christening.

Princess Charlotte, Christening

Chris Jackson - WPA Pool / Getty Images

The Princess of Cuteness is seen at her royal christening.

Kate Middleton, Catherine, Duchess of Cambridge, Royal Baby

Chris Jackson/Getty Images

Catherine, Duchess of Cambridge, is somehow more radiant than ever after giving birth to a daughter, her second child with Prince William.

 

Kate Middleton, Catherine, Duchess of Cambridge, Royal Baby, Prince William

Chris Jackson/Getty Images

Kate Middleton and Prince William introduce their new daughter to the world on the steps of St. Mary's Hospital in London, almost two years since they did the same with son Prince George.

Kate Middleton, Catherine, Duchess of Cambridge, Royal Baby, Prince William

John Stillwell/PA Wire

This face! Kate and Will's new daughter is fourth in line to the throne and already queen of Cutie Town.

 

Kate Middleton, Catherine, Duchess of Cambridge, Princess Charlotte, Prince William

John Stillwell - WPA Pool/Getty Images

Someone's on speed dial! Kate opts once again for a Jenny Packham dress to celebrate this major milestone.

 

Kate Middleton, Catherine, Duchess of Cambridge, Princess Charlotte, Prince William

Ian Gavan/Getty Images

The Duke and Duchess of Cambridge share a "private" moment as the world watches.

Kate Middleton, Catherine, Duchess of Cambridge, Royal Baby, Prince William

AP Photo/Matt Dunham

The crowd that's been camped outside of St. Mary's for days are rewarded with the royal waves.

Kate Middleton, Catherine, Duchess of Cambridge, Royal Baby, Prince William

Chris Jackson/Getty Images

Dad grabs the carrier and Mom's hand as they take their daughter home to Kensington Palace.

Kate Middleton, Catherine, Duchess of Cambridge, Royal Baby, Prince William

AP Photo/Alastair Grant

We can't with this one. All we know is, we need Kate's cheerful Jenny Packham dress (or one like it, because the duchess' is, of course, bespoke) and a new white blanket, ASAP.

Kate Middleton, Catherine, Duchess of Cambridge, Royal Baby, Prince William

AP Photo/Alastair Grant

No. 2, shmumber 2. This moment is just as exciting as the first time around, as far as we're concerned.

NEXT GALLERY: More second-born royal siblings

What will William and Kate name their third child? Tell us your thoughts in the comments!

Don't miss E! News every Tuesday to Sunday at 6pm.

  • Share
  • Tweet
  • Share

We and our partners use cookies on this site to improve our service, perform analytics, personalize advertising, measure advertising performance, and remember website preferences. By using the site, you consent to these cookies. For more information on cookies including how to manage your consent visit our Cookie Policy.