Authorities said Mariano Castro, 56, began abusing the victim when she was 8 years old. At 11, the victim gave birth as a result of the molestations. Shortly after giving birth, police said Castro resumed molesting the victim until she was 17 years old.
The victim, now 18, apparently came forward to police on advice of her priest.
After investigators spoke with Castro, he was booked for rape, lewd and lascivious acts and continuous sexual abuse of a child.
Police are also looking into the victim's mother's role in the case. Authorities say the victim told her about the abuse and the pregnancy but her mother remained married to Castro.
Castro is being held in a Santa Ana jail without bail.