Kate Middleton beams at Prince William as she returns to public life after cancer diagnosis

Kate Middleton's return to the public eye since her cancer diagnosis has proven to be successful, as the Princes of Wales has been all smiles during Trooping the Colour today.

First spotted arriving at Buckingham Palace by car on Saturday morning, the royal took to the palace balcony during the RAF flypast. The climax of the King's formal birthday event were met with cheering crowds who showed up to celebrate.

The 42 year-old was seen standing next to husband William and their three children - Prince George, Princess Charlotte and little Louis. As well as performing royal duties, Kate also had her hands full with youngest Louis, who has been seen getting into amusing mischief through the day.

Earlier, the mother-of-three had her hands full as she watched over her children during their carriage ride from Buckingham Palace to Horse Guards Parade for the military spectacle. Kate looked stunning in a white dress with navy trim by Jenny Packham, complemented by a wide-brimmed Philip Treacy hat and a sparkling Irish Guards brooch.

Crowds cheered as Kate waved from the glass coach that followed the carriage carrying King Charles and Queen Camilla to Horse Guards Parade. Camilla also wore a Philip Treacy hat and an Anna Valentine dress, reports the Mirror.

Other royals in carriages included the Duchess of Edinburgh, Lady Louise Windsor, and the Duke of Kent. Riding on horseback were Prince William, Princess Anne, and Prince Edward.

While enjoying the parade, young Prince Louis became the centre of attention as he was spotted getting distracted during the event. He was seen cheekily tugging on the blind cords while his mother, Kate, kept a watchful eye on him.

Rather than gazing out at the gathered crowds, he amusingly pulled on the white cord by the window.

Continuing with his playful behaviour, Louis attempted to lift the large white window in the office as the Duchess of Edinburgh looked on. With determination, Louis gritted his teeth and used both hands in an effort to push the window up, keen to get a better view from the balcony.

Not long after, Louis was caught yawning as he stood by the window in the Duke of Wellington's former office, watching the parade. The young prince arched his head back, hands clasped behind him, as he let out a sizeable yawn, while his sister Charlotte watched the proceedings with decorum.

Yet, intent on staying awake, he danced through the duration of the show. Louis swayed his hips and beamed a smile as his mother Kate chuckled behind him, and Charlotte seemed slightly vexed, whispering something to her brother.

The news broke on Friday that Kate would join the celebration for the King's official birthday alongside her family. In a heartfelt message, Kate expressed that she experiences "good days and bad days" while undergoing preventative chemotherapy treatment.

Accompanying her words, a stunning new photo taken by famed celebrity and Royal photographer Matt Porteous was released.

The Princess has expressed her intention to "hopes to join a few public engagements over the summer" while she continues her cancer treatment "for a few months". It's understood that Kate's participation in Trooping was motivated by her desire to show solidarity with her children, her family, and her affection for the King, who is also undergoing treatment for cancer.

In a heartfelt message, she conveyed: "I have been blown away by all the kind messages of support and encouragement over the last couple of months. It really has made the world of difference to William and me and has helped us both through some of the harder times. I am making good progress, but as anyone going through chemotherapy will know, there are good days and bad days."

She further shared her experience: "On those bad days you feel weak, tired and you have to give in to your body resting. But on the good days, when you feel stronger, you want to make the most of feeling well. My treatment is ongoing and will be for a few more months. On the days I feel well enough, it is a joy to engage with school life, spend personal time on the things that give me energy and positivity, as well as starting to do a little work from home.

"I'm looking forward to attending The King's Birthday Parade this weekend with my family and hope to join a few public engagements over the summer, but equally knowing I am not out of the woods yet. I am learning how to be patient, especially with uncertainty. Taking each day as it comes, listening to my body, and allowing myself to take this much needed time to heal. Thank you so much for your continued understanding, and to all of you who have so bravely shared your stories with me."

Before her announcement, Royal insiders confirmed that the princess had personally spoken to King Charles - who is also undergoing cancer treatment after being diagnosed with the disease in February - and informed him of her desire to join him and the Royal family for the parade. A spokesperson for the King said His Majesty was "delighted" by the news of her attendance.

Trooping the Colour marks Kate's first significant public appearance since Christmas Day last year when she walked to church with the rest of the Royal Family in Sandringham. In January, it was revealed she had undergone major abdominal surgery and then in March, in an emotional message to the world, she announced she had received a cancer diagnosis and was undergoing preventative chemotherapy.

Kate's schedule has been completely cleared for the remainder of the year as she receives treatment. The Princess was notably absent from the Colonel's Review on June 8, a key rehearsal for the Trooping the Colour parade.

As the honorary Colonel of the Irish Guards, Kate expressed her regrets for not being able to attend in a heartfelt letter to the regiment, wishing them the best of luck.

While Kate has taken a step back from public engagements during her recovery period, Prince William has continued to carry out official duties. During these appearances, the Prince of Wales has shared some reassuring news about his wife's condition.

During a visit to a suicide prevention organisation in Newcastle in April, Prince William engaged with members of the public. Julie Cain, aged 60, inquired about the wellbeing of his family, to which William responded: "All doing well, thank you. Yes, we're doing well."

Furthermore, last week, while attending the 80th anniversary D-Day commemorations in Portsmouth with King Charles and Queen Camilla, William offered another update. He mentioned that Kate would have been delighted to be there.

A video circulating on Twitter captured a moment where William, conversing with a veteran, seemed to confirm Kate's improving health by saying "she is" when asked if she was "getting any better".

The prince remarked: "She'd love to be here today."

He shared with the veteran that Kate's grandmother was employed at Bletchley Park during World War II, part of a group of women who "never spoke about anything until the very end", stating: "It was all very secret."

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