Love Blooms with the Duke by Alexa Aston

Xander Hughes, London’s biggest rake, suddenly finds himself in over his head, becoming the Duke of Brockbank and guardian to two nieces he has never met. He decides he must turn over a new leaf and become a sober, responsible duke and starts by hiring a governess for the girls. But Miss Fennimore is a most unique governess with her odd methods of education—and soon Xander wonders if she might make for an even better duchess.
Willa Fennimore’s parents were the toast of London’s theatre world until Theodosia Fennimore murdered her playwright husband and then leaped to her death. Not wishing to become an actress like her mother, Willa supports herself as a companion and governess for a decade, finding her latest post is to instruct a duke’s two unruly nieces.
As Willa falls in love with the orphaned girls, she finds herself also tumbling into love with the Duke of Brockbank. She’s been warned that the duke was a wild rogue before he inherited his title, but Willa only knows the caring man who meets his duties head on and spends an inordinate amount of time with his nieces, who aren’t so terrible after all.