The milestone arrives after a year that has brought both highs and lows

Meghan Markle is celebrating her 45th birthday today, reaching the midpoint of what was dubbed her "power decade" when she turned 40 five years ago.

The Duchess of Sussex is expected to spend the day at her California home with Prince Harry and their two children, Prince Archie, seven, and Princess Lilibet, five.

A friend told HELLO! that she was planning "a chilled day surrounded by loved ones".

The milestone arrives after a year that has brought both highs and lows. The family recently returned from a holiday in the UK and Portugal, and her guest appearance on MasterChef Australia delivered the programme's highest-ever ratings.

Yet the first half of her forties has been defined by the challenge of carving out a financially independent life beyond the royal fold, with results that remain decidedly mixed.

Her Netflix lifestyle programme, With Love, Meghan, has been axed following two series and a Christmas special, brought down by underwhelming viewing figures.

The As Ever brand, her range of fruit spreads and honey, has also failed to expand as anticipated.

Despite trademarking the business in Australia more than a year ago, and despite a week-long non-royal tour of the country with Harry in April, the products remain available only to American customers.

A new blackberry jam flavour, released days ago, represents the sole notable launch in months.

The duchess has instead leaned heavily on social media to promote her post-royal profile and drive sales, a strategy she appeared to acknowledge at a recent screening of Cookie Queens, an Archewell Productions documentary about Girl Scouts, where she praised the young entrepreneurs' use of digital tools to boost their businesses.

The family's recent visit to Britain carried significant emotional weight.

Prince Archie and Princess Lilibet met their grandfather King Charles at Highgrove House, but the trip left its mark.

Sources who spoke to People magazine said Meghan felt "a lot of sadness" about how events unfolded.

A friend close to Harry told The Times the return was "not how he wanted it".

Had the prince obtained the taxpayer-funded security he has been seeking, the children would have taken part in public engagements.

This would have been a dramatic shift for a couple who have fiercely guarded their offspring's privacy, never showing their faces in full on social media.

Meghan had initially intended to appear publicly alongside Harry during the trip but ultimately decided against it over security concerns.

The duke is pressing ahead with his campaign for the government to review his security arrangements and is planning another trip to the UK in September.

He is also hoping that King Charles will attend the next Invictus Games in Birmingham.

Having Meghan and the children alongside him at the event would represent a significant personal triumph for Harry.

A second royal reunion within months could yet materialise if the security impasse shifts.

The trajectory of the next five years looks set to be just as consequential as the first half of her forties.

Since leaving the Royal Family six years ago, Meghan's career has spanned television, podcasts, fashion and lifestyle branding, with persistent speculation about a possible return to acting.

Her immediate future appears firmly centred on strengthening her commercial presence in the United States, where she has rebuilt her life from scratch since turning 40.

Yet the prospect of more frequent visits to Britain has not been ruled out.