She doesn't tell him that she was married before to a violent alcoholic named Patrick O'Connor.
Hazel's sad past is now the Forrest's family secret.
This causes Hazel's father, Arthur Forrest, to visit James.
He explains that Hazel was previously married to a drunk, Patrick O'Connor, who beat her.
Mr. Forrest wants his daughter to be happy, while the prickly Mrs. Forrest is sure the Bellamys would never accept Hazel as a divorced woman (divorce being the shocking, stigmatic thing it was in 1912).