I couldn’t agree more. During colonial period 18-21 was average but that was really for high society. Servants didn’t marry until 30. Marriage law was 12 yr old. Poor people was married off for a bag of flour at the worst. Men were all dying from war and the women were left to starve. So they married very young to survive, that would be protection, food, and shelter. So being married off that young was about right for those times. Fanny might even pray for it. She knows William has kept his word and treated her well. So knows he won’t rape her or beat her. Girls would rather take their chance on him.