My Fugitive Prince by Miriam Minger

Estelle Easton has not forgotten the courageous young man, Prince Valentin Chevalier, who saved her life when she was only fifteen years old. She has asked her brother-in-law Donovan, the Duke of Arundale, countless times over the past three years if he has received any letters from Valentin, but he has always said no. Has Valentin been able to elude the dangerous men who were sent to hunt him down? Will Estelle ever see her fugitive prince again?