The Cursed Earl (Marriage by Necessity Series: Book 2)
The hero believes he's under a family curse and that he'll die on his 25th birthday. With the clock ticking against him, he must marry so he can have an heir before that fateful day arrives.
This is Book 2 in the Marriage by Necessity Series.
Book 1: A Perilous Marriage
Book 2: The Cursed Earl
Book 3: Heiress of Misfortune