Prince Harry and Meghan Markle will make major alterations to their new home, but any changes to Frogmore Cottage will be kept sealed from the public.
The Windsor mansion the couple were gifted by the Queen needs extensive renovations before they move in - but exactly what they are having done is going to be kept a closely guarded secret.
It's not just privacy concerns for the Duke and Duchess of Sussex, but also fears for their safety and that of their child who would either just have been born or about to be born.
The 19th century building - which has previously housed royal staff - has reportedly fallen into disrepair and urgent planning applications have been lodged with the local council. The normally public documents won't see the light of day, however.
Security concerns mean a special note on the application means it will be sealed to the public with the plans, architect drawings and any other documents unavailable for viewing, The Sun reported.
A note on the file states: "The application contains sensitive information and therefore the public register is not accompanied by any forms, drawings or supporting documents.
"The application will be advertised in the usual way but there is no additional information that is publicly disclosable."
It went on to say sensitive information was often submitted by "bodies such as the diplomatic community and owners of critical national infrastructure".
"These applications will often concern improvements to the physical security of the premises and may contain information which the applicant wishes the local planning authority to consider, but which the applicant does not wish to be made available on the planning register."
After the couple were married in a lavish ceremony in May, it emerged their countryside home in the Cotswolds was being guarded by special forces armed with machine guns with the same level of anti-terrorist security provided at Buckingham Palace and that protects UK Prime Minister Theresa May.
As well as the upgrades, the total cost of the project is also expected to be kept hidden. The work, which will cost millions of dollars, will be paid for from the Sovereign Grant which is the cash provided to the Queen from the Crown Estate.
Any work inside the home is expected to be paid for by Meghan and Harry themselves.
Harry and Meghan had their wedding reception at Frogmore House which stands near the cottage.
It is also where they had their engagement photos taken.
Frogmore is divided into five flats, meaning there will be plenty of room for Meghan's mum Doria Ragland to have her own space.
The former social worker is expected to stay with the couple on a regular basis and be a "hands-on" grandmother - but the Sussexes are also thought to have plans to have a live-in nanny.
Windsor Castle is just under a kilometre away from Frogmore Cottage, ensuring the new baby will close to the Queen, who will be its great-grandmother.
The Windsor Estate, where Frogmore Cottage sits, is about 32 kilometres from Kensington Palace, where until now Harry and Meghan have resided, very close to The Duke and Duchess of Cambridge and their niece and nephews.
A spokesman for the couple said in a statement: "Windsor is a very special place for Their Royal Highnesses and they are grateful that their official residence will be on the estate. The Duke and Duchess's office will continue to be based at Kensington Palace."
The cottage the pair currently live in was previously home to the Duke and Duchess of Cambridge before they moved into a 20-room apartment inside the Palace.