Prince William has been actively preparing for his role as the future King of the United Kingdom and other Commonwealth realms. But the longest role that he had been carrying is being a big brother to Prince Harry.

That being said, Prince William wants nothing but the best for Prince Harry. And an explosive new book is claiming that the Duke of Cambridge was worried about one key factor that made his younger brother rush to marrying Meghan Markle.

Prince Harry and Meghan Markle met through a blind date. The Duke of Sussex was known as the “Party Prince,” but he quickly cleaned up his act after dating the former actress.

A year later, Prince Harry and Meghan Markle announced their engagement. The couple, then, tied the knot at St George's Chapel, Windsor Castle, on May 19, 2018.

According to an upcoming book “Finding Freedom: Harry and Meghan and the Making of a Modern Royal Family,” Prince William did not want his brother to be exploited. Since the Princes had been taken advantage of because of their royal status, the source said that the Duke of Cambridge wanted to be sure that Meghan Markle had good intentions.

The book alleged that Prince William advised Prince Harry to take things slowly. He was reportedly worried that “lust” might push the Duke of Sussex to take his relationship with Meghan Markle to the next level so quickly.

“They’ve both developed a radar to detect that type of person, but as William didn’t know a whole lot about Meghan, he wanted to make sure Harry wasn’t blindsided by lust,” the source said.

Previous reports claimed that Prince William’s concerns regarding Prince Harry’s whirlwind romance with Meghan Markle started a feud between the royal brothers. The Duke of Sussex was, allegedly, upset that his brother did not seem to support his relationship with the American actress.

Royal fans, eventually, noticed that Prince William and Prince Harry were not as close as they were before. Rumors about the alleged rift began to spark even more when the Duke and Duchess of Sussex removed themselves from a joint foundation with the Cambridges.

As if that’s not enough, supporters of Prince William, Kate Middleton, Prince Harry, and Meghan Markle have been fighting online. Many were comparing the Cambridges and Sussexes, claiming that one couple is better than the other.