The name is the one Harry and Meghan chose to bestow their son Archie Harrison, which was also reportedly a touching nod to his great grandfather, the Duke of Edinburgh.
As a result, Meghan may opt to take on the same surname as her firstborn son so that they match, which would make her Meghan Mountbatten-Windsor.
The Mountbatten-Windsor name itself comes from the amalgamation of two family names – one being chosen by King George V and the other by Prince Philip.
King George V reportedly chose to take on the Windsor surname, while Philip opted for the Mountbatten surname after he married the Queen and became naturalised British citizen.
The two royal titles were eventually chosen to be used together as a result of tiff between the Duke of Edinburgh and the Queen over Philip's right to give his children his surname.
Taking to their Sussex Royal Instagram account on Sunday, the Duke and Duchess shared an emotional message to “honour mums all over the world”.
“Mummy. Mum. Mom. Mama. Granny. Nan. Thank you,” the message read.
An accompanying caption stated: “No matter what you call your mum, this Mother’s Day in the UK, we honour the mums all over the world who do so much every single day, and now more than ever.”