From Chapter 1 of
Persuasion"ELLIOT OF KELLYNCH-HALL.
"Walter Elliot, born March 1, 1760, married, July 15, 1784, Elizabeth, daughter of James Stevenson, Esq. of South Park, in the county of Gloucester; by which lady (who died 1800) he has issue Elizabeth, born June 1, 1785; Anne, born August 9, 1787; a still-born son, Nov. 5, 1789; Mary, born Nov. 20, 1791."
Precisely such had the paragraph originally stood from the printer's hands; but Sir Walter had improved it by adding, for the information of himself and his family, these words, after the date of Mary's birth -- "Married, December 16, 1810, Charles, son and heir of Charles Musgrove, Esq. of Uppercross, in the county of Somerset," and by inserting most accurately the day of the month on which he had lost his wife.
So Anne Elliot's sister Mary was married on Jane Austen's birthday, which also happened to be the date of Mrs Lefroy's death (Tom's aunt). The Elliots' mother's maiden name was Stevenson,
not spelled with a "ph", so it reminds us irresistibly of the village of Steventon, where Jane grew up. Jane also seems to have mined her mother's Leigh and Perrot ancestry in using the name Musgrove, although the actual surname was Musgrave (one of Jane's godparents was Mrs Musgrave).
However, the most interesting thing here is that the stillborn Elliot son was born on the same date that Tom Lefroy's brother Anthony married Elizabeth Wilkin. Son Elliot was born 5 November 1789, Anthony Lefroy was married on 5 November 1798. Coincidence? Given Jane's obsession with dates in both her letters and her fiction, and that she got news of other Lefroy marriages - "the third Miss Irish Lefroy" [Jane to Cassandra, 18 December, 1798] - I very much doubt it.