Jane is replying to Cassandra's letter announcing the death of Elizabeth, Edward's wife. The ladies at Southampton had already heard the news the day before: Mary (Lloyd) Austen, wife of James, had written a short note to her sister Martha, who was living w/ the Austen women.
Mrs James Austen travelled to Winchester to collect young Edward & George Knight, and take them back to Steventon for a short stay. Eleven children now motherless, youngest (Brook John) only a couple of weeks old and the oldest (Fanny) in her mid-teens.
This must have been a very difficult time for the entire family, and Jane was offering her emotional support as well as trying to be practical (offering to write letters, e.g.).