. HRH The Duchess of Sussex, wife of HRH Prince Henry Charles Albert David, Duke of Sussex, KCVO, gave birth to a daughter, Lilibet Diana, on Friday 4 June, 2021, at Santa Barbara Cottage, Santa Barbara, California, United States, a sister for Archie. The infant is eighth in line of succession to the throne.
By ancient custom, and courtesy of the Crown, the daughter of a duke in the Peerage of the United Kingdom is prefixed with the title 'Lady'. The new arrival in the House of Windsor is officially styled Lady Lilibet Diana Mountbatten-Windsor.
Much has been written since the Duchess of Sussex's recent explosive interview with Oprah Winfrey on the alleged 'snub' to Harry and Meghan's first child, Archie, and that he has been deprived of a title. I would suggest that the 'snub' here is on the other foot, and that it's the Sussexes who have snubbed the monarch in a churlish, and disrespectful manner. Harry and Meghan should be reminded that titles of courtesy come as courtesy from the Crown, and not from a parent.
The decision of the Duke and Duchess of Sussex to deny their son, and now their daughter, a courtesy title is I think unique in the annals of the peerage.
In a complete break with tradition and with the laws governing peerages, and the styles and titles of courtesy relating to the children of peers, it was announced in May, 2019 that Archie Mountbatten-Windsor would not use a courtesy title associated with the Dukedom of Sussex.
It was expected that Archie would be styled as Earl of Dumbarton, which is Prince Harry's earldom, created with the Dukedom of Sussex and Barony of Kilkeel in May, 2018. The eldest sons of dukes in the peerages of England, Scotland, Ireland, Great Britain and the United Kingdom traditionally assume their father's second senior peerage, as a 'courtesy' title. Some eldest sons decide to use a lesser title, as in the case of the eldest son of the Duke of Devonshire, who continues to be known as Earl of Burlington instead of the more senior Marquess of Hartington. If the Sussexes dislike the idea of Archie being Earl of Dumbarton then he could instead be known as Lord Kilkeel.
However, following Archie's birth, a statement quickly followed that no courtesy titles would be borne by the seventh in line to the throne, and that he would be known as Master Archie Harrison Mountbatten-Windsor.
The eldest son of a duke by custom uses one of his father's peerages as a 'courtesy' title, and he is also 'Lord' [Christian name] Surname, and was born so, and is recorded as such at the College of Arms in London. Similarly, the daughters of a duke are afforded the prefix of Lady.
Harry and Meghan's second child was born Lady Lilibet Mountbatten-Windsor. This courtesy title was not granted or bestowed by the Queen at birth as it is an automatic qualification. The 'courtesy title' comes as courtesy from the Crown, and not as a courtesy from a parent. If Harry and Meghan deny their daughter the courtesy title of a daughter of a duke they are in effect snubbing the Crown. Whether the courtesy title is used or not will not affect how the child's rank is recorded at the College of Arms.
In cases where a person succeeds to a peerage from a cousin or relation other than a parent then the siblings of that new peer do not automatically assume courtesy titles, and apply to the Crown to be so granted. Claims are reviewed and when approved the Crown Office issues the following:
'Her Majesty has been graciously pleased by Warrant under her Royal Signet and Sign Manual bearing the date …. to ordain and declare that …..(name of person seeking courtesy title) .. shall henceforth have, hold and enjoy the same title, rank, place, pre-eminence and precedence as the children of a ….Duke/Marquess/Earl/Viscount/Baron... as would have been due to them had their father … (his name)… succeeded to the title and dignity of Duke of …….and to command that the said Royal Concession and Declaration be recorded in Her Majesty's College of Arms.'
Archie Mountbatten-Windsor, being born the son of Duke, was born Lord Archie Harrison Mountbatten-Windsor as a legal entity. His sister enjoys the status befitting the daughter of the Duke of Sussex.
The Queen, Head of the Royal House of Windsor, declared by Letters Patent in 1960 that her male line descendants who were not Royal Highnesses or princes or princesses would have the surname Mountbatten-Windsor, to complement her husband, Prince Philip, who had assumed the surname of Mountbatten when he was naturalized a British subject in 1947.
Harry and Meghan's children now share this surname with the children of the Earl and Countess of Wessex, who, as children of the Sovereign's son are officially HRH, but do not use the royal style and title. Instead Edward and Sophie's children use courtesy titles derived from their father's peerages, and are known as Viscount Severn and Lady Louise Windsor.
Several peers, or relatives of peers with courtesy titles, do decide not to be so styled. And of course peerages can be disclaimed, within a time limit, under the terms of the Peerages Act 1963. Peers in the Peerage of Ireland and baronets cannot disclaim under the terms of the act. However, a man or woman who has been created a peer, as Harry was in 2018, cannot then go on to disclaim.
The younger children of dukes and marquesses are prefixed 'Lord' or 'Lady'. The younger sons of Earls, Viscounts and Barons are prefixed 'The Honourable'. Daughters of Earls are 'Lady', and the daughters of Viscounts and Barons are 'The Honourable'.
Lady Lilibet is the fifth grandchild of the Prince of Wales and is eighth in line of succession to the throne, and will follow her grandfather, Charles, then the Duke of Cambridge, Prince George, Princess Charlotte, Prince Louis and then her father, the Duke of Sussex, and elder brother Archie, in the line of succession.
The infant will be the eleventh great-grandchild of the Queen, and will not be born a prince or princess with the qualification of Royal Highness. That rank is reserved only for the children and male line grandchildren of the Sovereign, and the children of the eldest son of the Prince of Wales, as laid down by the Letters Patent of King George V , and the further Letters Patent of Queen Elizabeth II .
Under the terms of the Letters Patent creating Harry's dukedom, in May, 2018, the descent of the title is vested in his heirs male 'lawfully begotten'. Archie is destined, should he survive his father, to succeed as 2nd Duke of Sussex, Earl of Dumbarton and Baron Kilkeel. Lady Lilibet is not in remainder to her father's dukedom, earldom or barony.
The Queen's great-grandchildren:-
 Savannah Anne Kathleen Phillips [born 29 Dec 2010]
 Isla Elizabeth Phillips [born 29 March, 2012]
 HRH Prince George of Cambridge [born 22 July, 2013]
 Mia Grace Tindall [born 17 January, 2014]
 HRH Princess Charlotte of Cambridge [born 2 May, 2015]
 HRH Prince Louis of Cambridge [born 23 April, 2018]
 Lena Elizabeth Tindall [born 18 June, 2018]
 Archie Harrison Mountbatten-Windsor [born 6 May, 2019]
 August Philip Hawke Brooksbank [born 9 February, 2021]
 Lucas Philip Tindall [born 21 March, 2021]
 Lilibet Diana Mountbatten-Windsor [born 4 June, 2021]