Melissa Oliver 
Knight’s Substitute Bride [EPUB ebook] 

Could the wrong bride…Be right for him after all!For the sake of his family name, Lord Robert must marry to seal an alliance with an Irish clan. Only, the woman at the altar isn’t who he was promised! Instead, it’s her sister, Lady Mairenn! The sharp-tongued Irish beauty is as reluctant to wed as Robert, but as friction turns to fire between them, she’s further derailing Robert’s plans for this purely pragmatic arrangement…