"They were of a respectable family in the north of England; a circumstance more deeply impressed on their memories than that their brother's fortune and their own had been acquired by trade.
Mr. Bingley inherited property to the amount of nearly an hundred thousand pounds from his father, who had intended to purchase an estate, but did not live to do it."
While JA does not specifically say that it was Bingley's father who acquired the fortune, rather than perhaps his grandfather, do we assume that it was the father because he had not had time to purchase an estate? Could in fact the Bingley's new money have had an opportunity to age?