Prince William and Kate Middleton were college sweethearts, but the Duchess of Cambridge did not wear her first tiara and walk down the aisle at Westminster Abbey until she was 29.

Once the couple finally declared their royal engagement in November 2010, Prince Charles quipped, "They have been practicing long enough."

Royal author Katie Nicholl of "The Making of a Royal Romance" divulged that the Duke of Cambridge did not want to settle down at a young age. When questioned about tying the knot in 2005, the prince said, he was only 22 at the time, which was too young to marry for his age. He did not want to get married until he was at least 28 or perhaps 30.

Prince William's family appeared convinced that Middleton was The One and were assured she would make a pleasant addition to the British royal family.

With a different approach from his parents and brother, the duke bided his time until the pair had known each other for 10 years before exchanging vows at Westminster Abbey.

Prince William and Middleton were good friends at university and lived together before their romance bloomed, so several people anticipated he would pop the question and there was apparently much pressure on him to do so.

The prince also believed that his brother Prince Harry would get hitched before him.

Nicholl commented, "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."

Prince William refused the nudging of people and his reasoning was reportedly down to his parents.

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The royal expert asserted that Prince William pledged he would not be pressured into marriage before he was ready.

She also affirmed that Middleton insisted she did not urgently need to get married to him.

The book claimed that the future King was also dubious to make the duchess his wife because he knew from experience that his father, Prince Charles, had been forced into marrying his mother, Princess Diana.

Prince William learned from the ill-fated relationship of his parents and was resolute he would not go down the same path.

Nicholl wrote in the book, "He was reluctant to bow to similar pressure and vowed not to be hurried at the altar. He made his feelings clear, telling a journalist in an off-guard moment that he had no plans of getting married any time soon."

When he decided the timing was right, the duke then proposed to the duchess on a holiday in Kenya in 2010, with Middleton calling him a "true romantic." This was a month prior to the official announcement when Prince William whisked Middleton off to Kenya and traveled around the country before departing to Lake Rutundu.

Nicholl wrote that he booked a log cabin for the couple's stay and they spent the day unsuccessfully fishing for rainbow trout.

They were finally married at Westminster Abbey in London in 2011 after 8 years of being in a relationship.

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