Diana Palmer 
Unbridled 

He’ll endanger everything for her Widowed Texas Ranger and single dad John Ruiz hardened his heart years ago. Day after day, he tracks the toughest criminals in the Lone Star state, leaving little room for love. So when John butts heads with beautiful nurse who’s helping his young son, he’s floored by how quickly the sparks fly.Ever since her mother’s and brother’s brutal murders, Sunny Marlowe has devoted her life to helping save others. Adorable Tonio Ruiz is just another youngster she’s trying to help-or so she tells herself. Little does she know he’s John’s son. When her life comes under fire, can one mysterious rancher rescue her?