Lady Agatha Danbury is one of the fierce women in the "Bridgerton" universe and has close ties with Queen Charlotte. "Queen Charlotte" allows viewers to see their friendship from the start, as Agatha teaches the young queen about London society.
While "Bridgerton" fans already know Lady Danbury is a widow, the prequel answers questions about the nature of her and her husband's relationship, why she never remarries, and the "discreet" love affair she experiences after his death.
In the "Bridgerton" timeline, viewers see Lady Danbury and Violet Bridgerton connect as they come to terms with that affair, as Violet becomes privy to the fact that Lady Danbury romanced her father, Lord Ledger.