The Duke and Duchess of Cambridge said they are "delighted" to have become an auntie and uncle for a second time.
Meghan Markle and Prince Harry's baby boy arrived yesterday morning,
But Kate and Wills haven't had a chance to meet their little nephew yet, which also probably means big cousins Prince George, Princess Charlotte and Prince Louis are also still waiting to say hello.
During a visit to the Cutty Sark in Greenwich , London, this afternoon, they said they haven't had a chance to pop over to Frogmore Cottage to see the new parents and the baby boy yet.
Rather than rushing straight over, they've decided to wait until things have calmed down a bit.
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William said: "Obviously thrilled, absolutely thrilled, and obviously looking forward to seeing them in the next few days when things have quietened down.
"I'm very pleased and glad to welcome my own brother into the sleep deprivation society that is parenting."
Kate also revealed that they still haven't been told if Harry and Meghan have picked a name yet.
She said: "As William said, we're looking forward to meeting him and finding out what his name's going to be so so it's really exciting for both of them and we wish them all the best.
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"These next few weeks are always a bit daunting the first time round so we wish them all the best."
Prince Charles and Camilla also said they're yet to met the baby during their visit to Berlin.
Charles said: "We couldn't be more delighted at the news and we're looking forward to meeting the baby when we return."
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Meghan's mum Doria Ragland is staying with the couple at Frogmore Cottage so Baby Sussex has already had the chance to meet one grandparent.
The Queen was also out and about today, but didn't mention if she had had an opportunity to meet her great-grandchild yet.
