Queen Elizabeth II reportedly have a difficult relationship with Prince William.

The Duke of Cambridge is second-in-line to the throne. He is expected to reign after Prince Charles. Due to his future role, Queen Elizabeth II and Prince William reportedly share a “complicated” relationship.

“William is going to become king, so there has been a very close relationship between William and the Queen. It’s half family and half business,” E! News royal correspondent Melanie Bromley about the two royals’ relationship.

Royal author Juliet Rieden also believed that the Queen and duke’s relationship has become difficult due to their responsibilities in the monarchy.

“The Queen is 93 and she’s offloading a lot of her work both to her son and to her grandson,” Rieden said.

“The Queen is 93 and she’s offloading a lot of her work both to her son and to her grandson. William has really had to up the ante and take on a lot of this heavy lifting.”

The Queen has trained Prince William for his future role since he was 5. According to royal historian Robert Lacey, they share a special bond because Her Majesty has taken a particular interest in Prince William and has been teaching him the ropes to be the next monarch since he was a boy.

“When William became a teenager, she would have him at Windsor Castle and would open the state boxes and guide him through the papers,” Lacey told People. “It was William’s constitutional education.”

Prince William reportedly considered his grandmother the best role model. He once said that the Queen is a “soft influencing modest kind of guidance.”

Meanwhile, Christopher Anderson believed that if Queen Elizabeth II has a favorite grandson, it would be Prince William. According to him, in his book “William and Kate: A Royal Love Story,” the monarch rooted for Middleton. She reportedly found the Duchess of Cambridge “a suitable soulmate for her favorite grandson.”

Queen Elizabeth and Prince William
Queen Elizabeth II worried about Prince William. The Duke of Cambridge is pictured during “The Patron’s Lunch” celebrations for The Queen’s 90th birthday on June 12, 2016 in London, England. Jeff Spicer/Getty Images