George III’s longest-living daughter and Louis XIII’s younger brother also share their birthdays on 25 April.
Gaston, Duke of Orléans, born 1608
Gaston of France, the third son of Henry IV of France and his second wife, Marie de’ Medici, was born in 1608, although some sources have his birthdate as 24 April.
He was about eighteen months older than his youngest sister, Henrietta-Maria, who later married Charles I of England, Scotland and Ireland.
His father was assassinated in 1610 when his coach was stuck in traffic following his mother’s coronation ceremony in Paris.
Gaston’s older brother, aged 9, ascended the French throne as Louis XIII, with his mother acting as Regent until 1617.
He married wealthy French noblewoman Marie de Bourbon, Duchess of Montpensier, on 6 August 1626, after a lengthy betrothal since they were both toddlers.
However, Gaston’s wife died six days after giving birth to their only child, a daughter Anne Marie Louise d’Orléans, Duchess of Montpensier, on 4 June 1627.
Anne Marie, later known as the Grand Madamoiselle, was considered as a wife for his nephew, Charles II, during the 1650s.
He became the heir-presumptive from 1611, following the death of an older brother Nicolas Henri, until the birth of his nephew, Louis XIV, in 1638.
Gaston was involved in various plots against his older brother’s government and Prime Minister Cardinal Richelieu.
His political intrigues waging an unsuccessful war against Languedoc, taking refuge in Flanders until he reconciled with his brother.
A plot to assassinate Cardinal Richelieu which went awry, with Gaston abandoning his accomplices, fleeing into exile before another reconciliation with Louis XIII and the Cardinal.
He also secretly married his second wife, Marguerite, sister of Charles IV, Duke of Lorraine, whilst in exile after Louis XIII refused to grant permission.
Lorraine was an enemy of France at the time so the marriage was kept secret until he was betrayed when his brother and Cardinal Richelieu, who then declared the union null and void in parliament.
Louis XIII forgave Gaston and authorised his marriage to Marguerite on his deathbed in May 1643.
Gaston and Marguerite remarried in July 1643 and were finally accepted at court.
They had five children, with three daughters surviving into adulthood.
Gaston also fought in the border wars between France and Spain, as well as the wars of the Fronde against his nephew, Louis XIV, during the 1640s and 1650s.
He was exiled to his country home, the Chateau de Blois, in 1652 and remained there until he died from a stroke on 2 February 1660, aged 51.
Princess Mary, Duchess of Gloucester and Edinburgh, born 1776
Princess Mary was born at the Queen’s House (now Buckingham Palace) on 25 April 1776, the fourth daughter and eleventh child of King George III and his wife, Charlotte of Mecklenburg-Strelitz.
According to Flora Fraser, Princess Mary was considered to be George III’s most beautiful daughter, although ‘a bland beauty’.
Queen Charlotte took charge of her daughters’ welfare, education and moral values and appointed Lady Charlotte Finch as their governess and to manage the nursery when she was busy with official duties.
Princess Mary fell in love with exiled Prince Frederick of Orange-Nassau when the Dutch Royal Family fled to London in 1795.
However, George III suggested Mary should wait until her three older sisters were married first.
Prince Frederik died from a fever whilst serving in the Austrian Army in Padua, Italy, on 6 January 1799, aged 24.
Mary eventually married her cousin, Prince William Duke of Gloucester and Gloucester on 22 July 1816 in the Private Chapel at Buckingham Palace.
They lived at Bagshot Park until William’s death in 1834 but they had no children.
Queen Victoria invited Princess Mary to Osborne House, after the passing after another aunt, Sophia, had passed away in 1848, for some sea air and to play with the great-nieces and nephews, to help cope with her grief.
Princess Mary wrote to Queen Victoria, after attending the Great Exhibition in 1851, saying she was rather impressed and wrote of her admiration of the event.
She died on 30 April 1857, aged 81, at Gloucester House in Piccadilly, having outlived three kings (her father, brothers George IV and William IV) and was said to be Queen Victoria’s favourite aunt.
Princess Mary was the longest-surviving of all George III and Charlotte of Mecklenburg-Strelitz’s fifteen children.
Read more: Royalty Born on 25 April (Anzac Day)