Jane and the Christmas Masquerades — Sarah J. Waldock

This book comprises two novellas: 'Jane and the Vanishing Valet in which Jane and her family are invited to stay with Araminta's uncle for Christmas, only to have to discover why their host is struck down, and also what has happened to the new valet. 'Jane and the Unladylike Wife' in which a dinner party is given by a lady who is subsequently murdered, and Jane and Caleb must find out who has killed her and why, and who is the mysterious woman who called on her.