Prince William and Kate Middleton had secret marriage pact before they tied the knot

Prince William and Kate Middleton had a marriage pact. The pair made a promise to each other before their 2011 wedding.

• Prince William and Kate Middleton, Duchess of Cambridge had a secret marriage pact before they tied the knot.
• The Duke and Duchess made a promise to each other before they married back in 2011.
• In other royal news, Prince George and Princess Charlotte were spotted doing some exciting Halloween shopping with mum Kate Middleton.

Prince William and Kate Middleton, Duchess of Cambridge tied the knot back in 2011 and have since won over the hearts of royal fans all over the world.

Since marrying eight years ago the pair have welcomed three adorable children together, five-year-old Prince George, three-year-old Princess Charlotte and one-year-old Prince Louis.

But it turns out that the pair actually had a secret pact way before they tied the knot.

Revealing the private pact between the two in her royal biography Kate: The Future Queen, royal expert Katie Nicholl said that the young couple made an agreement that they would be each other’s safety net if they weren’t married by a certain age.

In her book she wrote that the pair said, “if we’re not married to anyone else by 40 then let’s tie the knot”, adding “let’s take the pressure off and just promise we’ll end up together”.

The pair apparently made the pact around the year 2007, not long after they had ended their relationship briefly and taken some time apart.

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The couple apparently flew to an island in the Seychelles to spend some quality time together and work on their relationship in private.

“There on the paradise island, William promised Kate that he was in the relationship for the long term,” Katie wrote in her book.

“For the very first time, they talked seriously about marriage, and with the ocean before them and beneath the night sky, they made a pact to marry.”

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Speaking in their engagement interview back in 2010, William mentioned the break in the couple’s relationship.

“We were both very young,” he said to interviewer Tom Bradby. “It was at university, we were sort of both finding ourselves as such and being different characters and stuff, it was very much trying to find our own way and we were growing up.”