Charles Stuart, Duke of Cambridge (1660–1661)
Charles Stuart( 22 October 16605 May 1661) was the first of four sons and eight children born from the marriage between the Duke of York( later James II of England& VII of Scotland) and his first wife, Anne Hyde.
He was styled" Duke of Cambridge", but never formally created so, because he died so young.
Edgar Stuart, Duke of Cambridge
Edgar Stuart, Duke of Cambridge( 14 September 1667 – 8 June 1671) was the fourth son of James, Duke of York( later James II of England) and his first wife Anne Hyde.
He was second in the line of succession to the English and Scottish thrones.
Edgar was born on 14 September 1667 at St James's Palace and baptized there with the Duke of Albemarle, the Marquis of Worcester, and the Countess of Suffolk as sponsors.
The name" Edgar" had ancient roots in both the English( Edgar the Peaceful) and Scottish( Edgar, King of Scotland) monarchies.
On 7 October 1667 he was created Duke and Earl of Cambridge and Baron of Dauntsey.
His elder brother Charles had died at the age of six months in 1661 before the patent for the title of Duke of Cambridge was passed and another brother, James was formally created Duke of Cambridge before his death in 1667 at the age of three.
Edgar ’s titles became extinct until the birth of another son, also named Charles, in 1677.
His mother was ill for months following his birth and never fully recovered, though she gave birth twice more to daughters who died before their first birthdays; she died on 13 March 1671.
Edgar died at Richmond Palace on 8 June 1671 and was entombed in the royal vault in the Henry VII Chapel in Westminster Abbey on 12 June 1671, his coffin placed atop that of his mother.
Charles Stuart, Duke of Kendal
Charles Stuart, Duke of Kendal( 4 July 1666 – 22 May 1667) was the third son of James, Duke of York( later James II of England) and his first wife Anne Hyde.
Charles was born on 4 July 1666 at St James's Palace.
His godparents were his three- year- old brother James, Duke of Cambridge, James, Duke of Monmouth and Emilia von Nassau, Countess of Ossory.
He was designated Duke of Kendal and was to have been created Duke of Kendal, Earl of Wigmore and Baron of Holdenby, but no patent was ever enrolled.
He died at St James's Palace at the age of 10 months on 22 May 1667 and was buried in Westminster Abbey on 30 May 1667.
Charles Stuart, Duke of Cambridge (1677)
Charles Stuart (7 November 167712 December 1677) was the first of two sons and third of seven children born from the marriage between James, Duke of York (later James II of England & VII of Scotland) and Mary of Modena.
He was styled "Duke of Cambridge", but never formally created so, because he died so young.
Charles Stuart (British Army officer, born 1810)
General Charles Stuart( 1810–1892) was a British politician and an officer in the British Army.
Mary of Modena
Mary of Modena  (Maria Beatrice Anna Margherita Isabella d'Este; –) was queen consort of England, Scotland, and Ireland as the second wife of James II and VII (1633–1701).
A devout Roman Catholic, Mary married the widowed James, who was then the younger brother and heir presumptive of Charles II (1630–1685).
She was uninterested in politics and devoted to James and their children, two of whom survived to adulthood: the Jacobite claimant to the thrones, James Francis Edward, and Louisa Maria Teresa.
Born a princess of the northwestern Italian Duchy of Modena, Mary is primarily remembered for the controversial birth of James Francis Edward, her only surviving son.
It was widely rumoured that he was a "changeling", brought into the birth chamber in a warming pan, in order to perpetuate her husband's Catholic Stuart dynasty.
Although the accusation was almost certainly false, and the subsequent Privy Council investigation affirmed this, James Francis Edward's birth was a contributing factor to the "Glorious Revolution", the revolution which deposed James II and VII and replaced him with his Protestant eldest daughter from his first marriage to Anne Hyde (1637–1671), Mary II.
She and her husband, William III of Orange, would reign jointly as "William and Mary".
Exiled to France, the "Queen over the water" – as the Jacobites called Mary – lived with her husband and children in the Château de Saint-Germain-en-Laye, provided by Louis XIV of France.
Mary was popular among Louis XIV's courtiers; James, however, was considered a bore.
In widowhood, Mary spent much time with the nuns at the Convent of Chaillot, where she and her daughter Louisa Maria Teresa spent their summers.
In 1701, when James II died, young James Francis Edward became king at age 13 in the eyes of the Jacobites.
As he was too young to assume the nominal reins of government, Mary represented him until he reached the age of 16.
When young James Francis Edward was asked to leave France as part of the settlement from the Treaty of Utrecht in 1713, which ended the War of the Spanish Succession (1701–1714), Mary of Modena stayed, despite having no family there, her daughter Louisa Maria Teresa having died of smallpox.
Fondly remembered by her French contemporaries, Mary died of breast cancer in 1718.
Princess Charlotte of Cambridge
Princess Charlotte of Cambridge( Charlotte Elizabeth Diana; born 2 May 2015) is a member of the British royal family.
She is the second child and only daughter of Prince William, Duke of Cambridge, and Catherine, Duchess of Cambridge.
She is fourth in the line of succession to the British throne.
Charles Stuart, 1st Baron Stuart de Rothesay
Charles Stuart, 1st Baron Stuart de Rothesay (2 January 1779 – 6 November 1845), known as Sir Charles Stuart between 1812 and 1828, was a British diplomat.
He was twice Ambassador to France and also served as Ambassador to Russia between 1841 and 1844.
Henry Stuart, Duke of Gloucester
Henry Stuart, Duke of Gloucester( 8 July 164013 September 1660) was the youngest son of Charles I, King of England, Scotland, and Ireland, and his wife, Henrietta Maria of France.
He is also known as Henry of Oatlands.
James Stuart, Duke of Cambridge
James Stuart, Duke of Cambridge KG( 12 July 1663 – 20 June 1667) was the second son of the Duke of York( later James II of England) and his first wife, Anne Hyde.
In 1664, the infant James became the first Duke of Cambridge and Baron of Dauntsey, titles his uncle, King Charles II, created especially for him.
The King also appointed Cambridge a Knight of the Garter, but never invested him due to his untimely death.
Cambridge received a yearly pension of £ 3,000 from the king.
Had Cambridge survived his early years, he would have been the first Protestant in the line of succession to the crown, ahead of his sisters Mary and Anne, when the" Glorious Revolution" of 1688 deposed his father and insisted on a Protestant succession.

Question: What is the cause of death of Charles Stuart, Duke Of Cambridge (1677)'s mother?
Answer: breast cancer