Meghan Markle and Prince Harry's new baby boy could help end the couple's reported "feud" with Prince William and Kate.
Baby Sussex's birth in the early hours of Monday morning saw champagne popping on the streets of Windsor, the Duke of Sussex addressing the media with a massive smile on his face, and pure joy echoing across the world.
The arrival of the couple's first child could be the glue that brings them closer to the Duke and Duchess of Cambridge, who live just 30 minutes drive away at Kensington Palace.
Kate and William, along with a host of other royals, said in a statement that they were "delighted with the news".
Relations have appeared strained in recent times, with Meghan, 37, and Harry, 34, abandoning their home next door to Kate and Wills in London to move to Frogmore Cottage in the grounds of Windsor Castle.
Rumours of the rift have driven a wedge between the "fab four", who are so popular with the public but reportedly very different.
But in becoming parents to a little boy, who is yet to appear in public, the Sussexes instantly have something more in common with the Cambridges.
Kate and William's children Prince George, 5, Princess Charlotte, 3, and Prince Louis, 1, will be the perfect playmates for their new cousin.
While the couple is not expected to be named as godparents, they could be a great support to the new parents, who are reportedly not hiring a nanny.
Few details are known as to the baby's name, title, and where the family will be based long-term, but they are set to appear together in the next few days.
The bookmakers' favourite names include Arthur, Albert, James, Phillip and Alexander.
It is a very different start to parenthood than the one the Duke and Duchess of Cambridge experienced on the steps of the Lindo wing of St Mary's Hospital, and we are likely to see the break with tradition continue.
They will, however, face the same pressures and scrutiny as new parents that Kate and William will be best able to relate to.
Meghan intends to return to public duties in a few months after finishing her maternity leave.
Until then, she has her mother Doria Ragland by her side at Frogmore Cottage.
Ms Ragland is said to be "overjoyed" at the arrival of her first grandchild.
But the baby's maternal grandfather was notably absent, with Thomas Markle alienated from the couple after his antagonistic comments to the media.
Mr Markle told TMZ he would not head to the UK to meet his grandson, with the gossip site reporting this was because he was "persona non grata" and in the "cone of silence".
The newest little royal hasn't automatically been born into a title, despite dad Harry's "prince" status.
According to King George V's 1917 decree, only the eldest son of the Prince of Wales' eldest son (so Prince George) was entitled to be called His Royal Highness and a Prince.
In late 2012, the Queen amended the rule, declaring that all of Prince William and Kate Middleton's children would be titled HRH, either prince or princess.
At that time, the ruling didn't apply to any of Prince Harry's children — so unless a change is made, this new bub will be styled as Lord Mountbatten-Windsor and the Earl of Dumbarton.
Harry himself has indicated he wants his children to have as normal lives as possible.