Prince Harry swiftly returned to the United States after attending his father, King Charles III's Coronation, to celebrate his son Archie's birthday.
The Duke of Sussex flew to the UK for just 28 hours to witness the lavish ceremony in Westminster Abbey on Saturday.
He was then seen boarding a British Airways flight from Heathrow Airport, which landed in Los Angeles at 7.30pm local time on Saturday
Archie turned four years old on Saturday, and his mother, Meghan Markle, planned a low-key party for him at their home in Montecito, California.
Meghan reportedly felt that attending the historic event at Westminster Abbey would have been "inauthentic," and she wanted to "minimize the drama."
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So, she held a "low-key" birthday party for Archie at home which he enjoyed with his family as his sister, Lilibet, who turns two in June, also joined in the fun.
The celebrations were small and intimate, with only Archie's grandmother, Doria Ragland, and Meghan's close friend, Victoria Jackson, in attendance.
It is not confirmed whether any other celebrity neighbours, such as Oprah Winfrey, attended.
But in a special touch, Meghan baked a lemon cake for Archie using fruit from their garden, a source told the Mail.
The couple's £11million home in Montecito was decorated for the occasion, with balloons and streamers adding to the festive atmosphere.
Harry's appearance at the coronation on Saturday was his first public appearance alongside the royals since the publication of his memoir "Spare."
He was seated in the third row, two rows behind his brother Prince William, and did not appear on the Buckingham Palace balcony with King Charles and his stepmother Camilla, the Queen Consort.
What could Archie's party have been like?
In the lavish area of Montecito, California, which is inhabited by high-profile residents, celebrities and multi-millionaires, children's birthday parties can be wildly extravagant, an insider has claimed.
Gatherings could entail six-figure spending on 50ft-wide painted backdrops, food trucks, Ferris wheels, and vast balloon garlands, says Lisa Gaché, an LA-based author who teaches children's etiquette classes at the Montecito Club.
Otherwise, Ms Gaché suggested that parties can be more down-to-earth and modest, with a few blow-up balloons, a homemade cake covered in raspberries, and a charmingly low-key celebration.
The author explained that while Montecito residents have access to wealth, there is also a sense of 'down-to-earth'-ness that can result in less of a desire to put on ultra-lavish affairs.
“The residents there tend to come from older money, and that means a different approach,” Ms Gaché told the Telegraph.
She also noted that children's parties in Montecito are "fixated" on safety and dietary restrictions, with party favours carrying ethically sourced toys from companies like Jessica Alba’s Honest, which promotes “clean living for mamas and babies”.
“There are emails in advance about making sure there is no gluten on the premises, even if no children are gluten-intolerant,” Ms Gaché said, adding: “In this neck of the woods, we have so many children who are vegetarian or keto or paleo, and they need to be aware of that."
Alcohol is also frowned upon for kids' parties in Montecito, and there's a strong focus on mental health and raising kids in an appropriate manner, the author said.
From her side, Leesa Zelken, the founder of LA-based party planner Send in the Clowns, mentioned that people in Montecito are not embarrassed to spend serious money on kids’ parties and that an over-the-top look is applauded.
She said that her clients regularly have a balloon budget of around $10,000 and have done everything from installing ice-skating rinks to training actors to recreate classic Disney films.
Asked if she were hired to organize Prince Archie's birthday, this is how she would do it: "I would lean into something all-American.
"They have embraced being here – the party should reflect that. It’s also the perfect time of year for a fair with hot dogs and picnic tables. Things that feel very celebratory of their new life, not their old one."
