India, Aug. 18 -- King Charles III and Princess Diana's marriage was rocky from the beginning. Married in 1981, they were nearly 13 years apart in age and had very little in common. While Diana struggled with her role in the royal family during the mid-1980s, Charles was rekindling his relationship with Camilla Parker Bowles.

By 1991, Diana and Charles' marriage was unravelling, but one shocking incident involving their eldest son, Prince William, was the final nail in the coffin, which eventually led to the collapse of their marriage.

According to The List, on June 3, 1991, eight-year-old Prince William suffered a severe blow to the head while playing golf with his schoolmate at Ludgrove School. He was rushed to Royal Berkshire Hospita...