Queen Elizabeth II and Prince Philip waited for a decade to have more kids after Princess Anne.

Princess Anne was born on Aug. 15, 1950, and her younger brothers Prince Andrew and Prince Edward were born in 1960 and 1964, respectively. According to royal biographer Sally Bedell Smith in her 2012 book “Elizabeth the Queen,” there’s a heartbreaking reason Her Majesty waited for 10 years before welcoming a new baby to their family.

Smith revealed that Prince Philip and Queen Elizabeth II halted having kids due to a lengthy family feud. When Queen Elizabeth II ascended to the throne in 1952, the Duke of Edinburgh wanted his kids to take his family name Mountbatten, but the royals rejected his proposal.

Former Prime Minister Winston Churchill, Queen Elizabeth II’s grandmother Queen Mary and mom Queen Mother all strongly believed that the members of the Royal Family remain a Windsor. Queen Elizabeth II sided with her family and rejected her husband’s request.

In that year, the monarch issued a public declaration announcing that “her children will be styled and known as the house and family of Windsor.” It left Prince Philip devastated.

The 97-year-old royal didn’t take the issue lightly. He felt that he was the “only man in the country not allowed to give his name to his own children.”

Earl Mountbatten told Smith that the 10-year delay of welcoming more royal kids after Princess Anne was due to Prince Philip’s discontent over the surname issue. When Queen Elizabeth II was already expecting Prince Andrew, she visited former Prime Minister Harrold Macmillan over the same issue concerning the royal children’s family name because it had been irritating the Queen’s husband since 1952.

“The Queen only wishes (properly enough) to do something to please her husband – with whom she is desperately in love,” Macmillan wrote in his diary.

“What upsets me is the prince's almost brutal attitude to the Queen over all this,” he added of Prince Philip’s treatment toward the Queen.

Prince Philip and Queen Elizabeth II’s relationship changes depending on the setting. When they are in public, Prince Philip reportedly allows the Queen to lead. However, once they are inside their house and the doors are closed, the Duke of Edinburgh becomes the boss.