What does Douglass say about the sexual relationships existed in his narrative?

Slave children always followed the condition of their mother, a fact Douglass noted was no doubt due to slaveowners' pernicious lustful designs upon slave women. Children born from slave mothers and white fathers – mulattos – experienced far more difficulties than did other children. They must always fear the wrath of the slaveowner's wife; their presence was a constant reminder of her husband's infidelity. The slaveowner himself must watch his white sons abuse their black brothers. It is actually best if he sells these children to another slaveholder.

The fact that there were so many mulattos present in the Americas who are held in slavery refutes the belief that "God cursed Ham, and therefore American slavery is right. If the lineal descendants of Ham are alone to be scripturally enslaved, it is certain that slavery at the south must soon become unscriptural..."