In the book Kate: The Future Queen, author and royal expert Katie Nicholl explains why the event brought some sadness for Kate.
Ms Nicholl shares that while Will proposed on October 20, 2010, the couple decided to wait a few weeks before making a public announcement on November 3.
During this time, the couple didn't tell many people about their happy news, including close friends and family as they were worried the news would leak before they were ready to make an announcement. However, this is the cause of upset for Kate.
Between getting engaged and making the announcement, Kate's last living grandparent, her grandfather Peter, passed away, just one day before they were set to make the announcement and share the happy news.
"Kate was deeply saddened not to have had the chance to tell her grandfather that she was engaged to William," Ms Nicholl wrote, according to The Mirror. "She knew he would have been delighted for her."
The couple delayed their announcement and attended the funeral together, deciding to tell their family and friends on November 16, hours before the news was made public.
In another of Ms Nicholl's books, The Making of a Royal Romance, she shares that William was hesitant to propose to Kate as he was aware his father had been pressured into marrying his mother Princess Diana.
"He was aware his father had been pressured into marrying Diana because she was deemed the suitable bride. He was reluctant to bow to similar pressure and vowed not to be hurried to the altar," explains Ms Nicholl.
According to the International Business Times, William was quoted in 2005 as saying, "Look, I’m only 22 for God’s sake. I’m too young to marry at my age. I don’t want to get married until I am at least 28 or maybe 30."
"He made his feelings clear, telling a journalist in an off-guard moment that he had no plans of getting married any time soon," Ms Nicholl wrote in her book.
William even joked that he thought his brother Prince Harry might even settle down first, which we now know did not happen as he married Meghan Markle in 2018.
Thankfully, it doesn't seem as though Kate was offended by the comment, "If it hurt Kate when William hinted that his younger brother Harry was more likely to tie the knot before they would, she didn’t show it," the author wrote.
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