Waving and smiling, the Princess of Wales delighted the gathered crowds when she appeared at Trooping the Colour for King Charles’ birthday celebrations. After six months out of the spotlight, it was a careful comeback after abdominal surgery and then cancer had turned her life, and that of her young family, upside down. As she stepped down from the Glass State Coach, it was a tentative first step back into public life.

But this was not a signal that things are back to business as usual. Kensington Palace were quick to brief royal reporters that no decisions had been made on any future engagements over the coming months, and the Princess would only attend events as and when she felt able to, with the guidance of her medical team.

As Kate herself said in a statement: ‘I am making good progress, but as anyone going through chemotherapy will know, there are good days and bad days. 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.’

Her treatment is ongoing, and will be for the next few months, but I understand she would like to visit the Wimbledon tennis tournament – she is its patron – if she feels up to it.

She also wants to support her children through their end of school sporting fixtures, picnics and outings. Her family are the ‘front and centre of her world’ and it is they who have kept her going. As one friend told me: ‘Family time is her absolute priority. It has been difficult shielding the children from some of the tougher aspects of her treatment, but they are her main driver in staying strong and keeping going. The three kiddies and William have been her sole focus and are her absolute world.’

After George, 10, Charlotte, 9 and Louis, six, break up from school the family will retreat to Anmer Hall and the soothing Norfolk countryside for the summer holidays. There they will celebrate George’s 11th birthday privately, while Kate will continue to do some light work from home including her Royal Foundation’s work on Early Childhood.

The Princess has found great solace in nature and being outdoors with her family. The choice of background of both the picture of her under a weeping willow to accompany her public statement, and the one released for Father’s Day with William and the children on a Norfolk beach, was no coincidence.

It’s expected that if she feels strong enough, the Wales family will visit the King at Balmoral at the end of August – but again this is private family time.

Her team are not yet planning any autumn engagements, as the priority is the Princess’s total recovery, and there is no time frame set for her return to full public duties. Yet she is feeling strong enough to hold meetings with her new Private Secretary Lieutenant Colonel Tom White, who previously worked for the late Queen Elizabeth as her equerry. It’s likely that her return to work will be phased and gradual, and probably not up to full strength until next year.

But the fact that she felt well enough to attend the King’s official birthday celebrations is a positive sign. There had been no guarantee that either the Princess or the King would be able to attend after both had been diagnosed with cancer this year.

Yet both were determined to put on a show of unity – a Royal Family reunited against the odds.
For Kate, her appearance, which was announced at the very last moment to ensure she was feeling strong enough, was an act of service; supporting her father-in-law – with whom she is very close – and her children. She wanted to be there for the ‘kiddies’ (as she calls them) as their father was riding on horseback in the parade, so she didn’t want them to have to ride solo in a state coach or be forced to skip it all together.

Later on the balcony, Charles had placed his daughter-in-law next to him, leaning in to make conversation time and again. As the day’s festivities drew to a close, the Duchess of Edinburgh patted Prince William reassuringly on the shoulder as the family walked back into Buckingham Palace together.

‘Well done, everyone,’ the King said, the sight of the cheering London crowds would have been an extra lift. Here was a Royal Family appearance like no other: tactile, together and very human.