In fact, it was reported at the time, the couple delayed their honeymoon just so they could toast the occasion, even though Prince Charles' actual birthday is in November.
On Sunday, however, it was reported that Prince Harry and Meghan Marklewill not be attending Prince Charles' special 70th birthday celebration, which is being partially organised by his wife, the Duchess of Cornwall, for October 25.
And we, as a nation, are a little to blame.
It's expected the Duke and Duchess will arrive in Sydney on October 16, before visiting rural NSW town Dubbo, then Melbourne, before returning back to Sydney for the opening ceremony of the Invictus Games.
They're then scheduled to visit the Queen’s Canopy project in Fraser Island - just off Queensland's eastern coast - on October 22, before heading to Fiji and Tonga.
The Duke and Duchess of Sussex will be back in the UK for Prince Charles' actual birthday, even if it does seem like they're missing out on a pretty elaborate bash.
According to invites, which, according to Vanity Fair, went our last week, the concert and dinner celebration will feature "a program of music, opera, ballet and Shakespearean drama," to celebrate the Duke of Wales' patronage of the arts.
Other celebrations for Prince Charles will also include a party hosted by the Queen herself in the State Rooms of Buckingham Palace on the date of his actual birthday, as well as a magic-themed gala show at the London Palladium, at which Charles will be the guest of honour.
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