Trouble by Lex Croucher

When her dear sister Amy falls ill, Emily reluctantly decides to go in her place to be the new governess at Fairmont House so Amy does not lose the position. Where Amy is kind to everyone and loves children, Emily is ornery and dislikes kids. However, the residents of Fairmont House are a quirky crew, and soon Emily finds herself liking her co-workers and having feelings for Captain Edwards, the widowed head of the household and father to two teenagers--Aster and Grace. Trouble is a delightful historical romance with a contemporary bent and is perfect for readers who enjoyed The Very Secret Society of Irregular Witches.