Prince Charles, Kate Middleton and Prince William
Prince Charles advised Prince William to break up with Kate Middleton after the Duke of Cambridge said that he was not ready to commit at 25. Pictured: Prince Charles, Middleton and Prince William share a joke during a visit to Dumfries House on March 05, 2013 in Ayrshire, Scotland. Getty Images/Danny Lawson

Prince Charles once advised Prince William to break up with Kate Middleton for a reason.

The Duke and Duchess of Cambridge dated for years before he popped the big question. However, even the Prince of Wales thought that their dating process was too long.

In the documentary “Kate Middleton: Biography,” royal author Christopher Andersen recalled how Prince William reportedly sought his father for advice. He was already 25 at the time, but he still felt that he was too young to get married. However, the future king didn’t feel the same.

“And Charles, who was by then very fond of Kate, said ‘it would be unfair to the young lady’,” Andersen said. “You cannot string her along anymore, so you should just break it off,” Prince Charles added, according to the royal expert.

Prince William indeed broke up with Middleton. The duchess was “reeling” when Prince William decided to end their five-year relationship. However, their split didn’t last long because they rekindled their romance after a few months.

During the split, Middleton flew to Dublin with her mom, Carole. The duo traveled with a group of friends. Middleton also met Irish Gemma Billington, a family friend.

They also visited her first exhibition at the Urban Retreat Gallery and National Gallery of Ireland. The visit didn’t come as a surprise since Middleton was known for her passion for art.

However, during the said visit, they came across reporters who wanted to interview Middleton. The media wasn’t aware of Middleton and Prince William’s split back then, so she "politely declined."

During their engagement interview, Prince William and Middleton spoke about their split. According to the Duke of Cambridge, they parted ways because they were still too young at the time and were figuring out what they wanted to do with their lives.

On the other hand, Middleton admitted that she wasn’t happy about their split. However, it helped her in some ways. According to the royal mother of three, it made her stronger and she found out new things about herself that she hadn’t realized when they were still together.