GettyImages-1051839484 (1)
Prince Harry reportedly once feared losing Prince William. The two are pictured attending the Illegal Wildlife Trade Conference at St. James’ Palace in London on Oct. 10, 2018. Tolga Akmen-WPA Pool/Getty Images

Though there are reports that they’ve been engaged in a feud since Prince William questioned the speed of Prince Harry’s relationship with Meghan Markle, at one point in their lives, Harry reportedly was worried that he could lose the relationship he had with his brother.

According to Katie Nicholl’s book “Harry: Life, Loss, and Love,” while the younger Prince was very happy when his brother announced his plans to marry Kate Middleton in 2010, there was a part of him that feared losing his brother in a small way.

“Harry adored Kate and, while he feared losing his brother to a degree, he was genuinely delighted for them,” she wrote.

The brothers still remained close over the years, even serving as one another’s Best Man at their individual weddings in 2011 and 2017. However, since Harry married Meghan Markle in 2018, there have been reports that the two brothers are no longer as close as they once were.

In the documentary “Princesses At War,” Nicholl also spoke out about the relationship between the siblings, stating that William was concerned by how quickly Harry’s relationship with the former actress had moved, but when he voiced his concerns, his younger brother took it as a criticism of his romance.

“What was meant as well-intended brotherly advice just riled Harry,” she said. "Harry is hugely protective of Meghan, he saw that as criticism, he interpreted that as his brother not really being behind this marriage. I don’t think things have been quite right ever since.”