Charles Brandon's illegitimate children

Charles Brandon (1483-1545), Duke of Suffolk, closest friend and brother-in-law of King Henry VIII. Charles Brandon had four marriages and eight legitimate children.
Charles also fathered three illegitimate children; Charles (1521-51), Frances (d.1600) and Mary. Coincidentally, these children share the same names as their legitimate half-siblings. The identity of the mothers of these illegitimate children are unknown. Judging by their dates of marriage, it seems likely that Charles and Frances were born during the Duke's marriage to Princess Mary Tudor, Queen of France, and Mary was born during his marriage to Catherine Willoughby.

Charles Brandon, Duke of Suffolk

Charles Brandon seems to have had a close relationship with his father Charles, the Duke, in particular during his adulthood. In November 1542 Charles commanded a garrison of 200 on the Scottish border where his father was Warden of the Marshes. Charles, then went to war in France with his father the Duke in 1544, where he knighted him in September in Boulogne. The Duke had also used his influence to grant him the stewardship of Sheriff Hutton in January 1544. In 1547 Charles became MP for Westmoreland.
Charles was of the Protestant faith; this can be seen in his support for the Dissolution and his poor treatment of the priests of the monastic lands he desired. Also, in his Will, his phrasing reveals a Protestant view to sin and death, rather than a Catholic one.
Between 1541 and 1545 Charles married Elizabeth Strangeways (1498-1559), nee Pigot, a widow of Sir James Strangeways (1503-41). Elizabeth was an heiress in her own right, of her uncle Sir Ralph Pigot (d.1503). After Charles' death she married for a third time to Francis Neville (1519-82). There were no children from any of Elizabeth's marriages. It was through his wife's inheritance that Charles gained Sigston Castle in Yorkshire which became his principal residence. In March 1546 Elizabeth's father Thomas died and she inherited a third of his estate. Charles and Elizabeth gained former monastic lands in Yorkshire; the manors of Appleton Wiske and Unerby, on the condition that Elizabeth give up her manor of Greenshaw.
Charles died on the 12th of August 1551 in Alnwick, after an illness of at least a month; he made his Will in July. In Charles' Will, he left his 'sister Sandon', Frances, some gold bracelets; indicating that the half-siblings shared a close relationship. It is possible that as Frances Sandon was the only sibling he named, the two were in fact full siblings, sharing the same mother as well as the same father.
After his wife Elizabeth, the main beneficiary of Charles' Will was his 'cousin' Humphrey Seckford and who he left Sigston to; an executor of his Will was Francis Seckford, Humphrey's brother, and another brother Anthong Seckford was left £10. The Brandon and Seckford families were related but very distantly, therefore this close relationship between the Seckfords and Charles could be interpreted as a close familial one; in that Charles' mother was a Seckford.

Frances Brandon married firstly William Sandon (1522-59). Frances and William had Katherine (b.1545), Anne, Frances and Ambrose (1557-1628).
Katherine Sandon married Edward Asfordby (d.1590) and had William (d.1623), John, Edward, George, Peregrine, Jane, Susan and Elizabeth. The use of the name Peregrine is interesting to note as Katherine Willoughby named her son Peregrine; perhaps reflecting the relationship between the family members.
William Sandon was Sheriff of Lincolnshire in 1544. In his Will of 9th October 1558, William mentions 'my wife's mother and my wife's brother'; as all of Duke Charles Brandon's sons were deceased by this time, we can assume that this is referring to Frances' mother and her son from another relationship. This also means that Frances shared a close relationship with her mother throughout her life. In his Will, William also leaves a bequest to 'my cousin Elizabeth Gildon, daughter of my uncle-in-law Thomas Gildon'; it seems unusual that he would refer to a husband of an aunt in his way, so it was perhaps that Thomas Gildon was an uncle of William's wife Frances. This would make Frances' mother a member of the Gildon family.
Frances' son Ambrose Sandon married a woman named Barbara (d.1627) and they had a son named Thomas (b.1599). However after this the Sandon line vanishes.
By 1562 Frances had remarried to Andrew Billesby.
Both of Frances' husbands were Lincolnshire gentlemen whose families were closely associated with each other due to geography and marriage. Both Sandon and Billesby knew and were supporters of Mary Willoughby, the mother of Duke Charles Brandon's fourth wife Katherine.

Mary Brandon married Robert Ball (b.1542). Robert was the son of John Ball (1518-56) and Mary Marsham. John Ball was a servant to the Willoughby family. Robert Ball attended Cambridge University in 1560. Very little is known about Mary Brandon.