The Gentleman's Guide to Vice and Virtue by Mackenzi Lee

The Gentleman's Guide to Vice and Virtue
Monty is a lord in the 1800s and is about to embark on a grand tour of Europe with his brainy sister Felicity and his best friend and fellow aristocrat, Percy.
The tour falls apart and becomes an adventure and a desperate attempt to retrieve an alchemical device that might save one of the three from a devastating condition and fate in a sanatorium. The French court, racial injustice, pirates, Venice, parental abuse, and unrequited love make for a fabulous narrative.
The three young protagonists learn to become heroes. Every character has a story. The romance is epic. A perfect read for anyone who likes a dash of history and romance with their adventure and Jane Austen.