Princess Charlotte Augusta of Wales (1796-1815) died from complications when giving birth to a stillborn child when she was just 21 years old. The last eighteen months of Charlotte's wife were blissful as the happy bride of Prince Leopold of Saxe-Coburg-Saalfeld. Her childhood prior to that was less pleasant. Though the only child in succession to become Queen of England, there was nothing in English law to protect her from her nutso parents. Charlotte was the only child of Prince George (eventual King George IV), and Caroline of Brunswick. The marriage between Caroline and George was a contentious failure and they used daughter Charlotte as a weapon against one another.
Charlotte was beloved by the citizens of England and her death left the country without an heir to the English throne. George's sons were urged to produce heirs. Prince Edward responded by marrying the sister of Charlotte's widow, Leopold, and the union produced Princess Victoria who became Queen of England in 1837 and ruled until 1901.