Hello everyone who just watched Sophie's backstory get revealed on Bridgerton—aka the moment the Earl of Penwood introduced her as "my ward" to his new wife, Araminta. However, based on Araminta's strong negative reaction to meeting Sophie (and the cruel way she treats her), it's safe to assume that Sophie is, in fact, the Earl of Penwood's "illegitimate" daughter. As the book's Fandom page notes, "she’s the illegitimate daughter of the Earl of Penwood. When she was three years old, she was dropped off at her father's estate in the country by her dying grandmother. In other words, Sophie is the Earl of Penwood's daughter!