Meghan Markle could be set to invite "a number of celebrities" to her son's birthday bash, which falls on the same day as King Charles' Coronation.
Fans will be waiting in anticipation for the moment the Duchess of Sussex releases official photos from the "intimate party" which is reportedly set for May 6.
Famous faces thought to be attending Prince Archie's fourth birthday party include Ellen DeGeneres, Serena Williams and even Orlando Bloom, according to a PR expert.
The day itself looks set to be a classic children's party and could include an outdoor picnic, face painting and a birthday cake.
"There's no doubt there will be famous friends at the party. The couple live in Montecito, which means they have a number of celebrity neighbours.
"Just as we would invite our neighbours to parties, if we were friendly with them, it's the same for the Duchesses," Mayah Riaz told The Mirror.
The 'PR to the stars' added: "We can probably expect Ellen DeGeneres and Portia de Rossi at the party, as the couple were at their vow renewal.
"We know the couple are friends with Serena Williams, Priyanka Chopra, and Jameela Jamil to name a few and it's possible if they were around they would be attending.
"If rumours are to be believed, then Harry texts Orlando Bloom about lurking paparazzi in the area, and it would be great to see photos of him at Archie’s party too."
Archie's party will take place in Montecito, California, with his dad expected to rush home after the King's Coronation so he can attend both events.
Speaking about what's in store, Mayah said: "If Lilibet's 1st birthday is anything to go by, we can possibly expect an intimate outdoor picnic amidst the couple's chickens, face painting, a classic birthday cake and surrounded by friends joining throughout the day."
She added: "If it's true that Harry and Meghan are holding a small, intimate party for Archie, this comes as no surprise.
"As we know, Harry won’t be around for Archie's actual birthday so this sounds a great way of celebrating whilst Harry is around."
Fans will be hoping to get a peak inside the party and will be hoping for some official pictures of the youngster.
It's traditional for royal households to release photo portraits on a family member's birthday - with the Sussexes doing this on every previous occasion for their son.
"We hope that the couple release official photos from Archie's 4th birthday party, so we get a glimpse of it," the PR expert added.
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