Princess Diana, Prince William, Prince Harry and Prince Charles
Princess Diana gave Prince Harry more love and attention compared to his older brother, Prince William. Pictured: Princess Diana, Prince Harry, Prince William and Prince Charles watch the parade march past as part of the commemorations of VJ Day on Aug. 19, 1995 in London. Getty Images/Johnny Eggitt

Princess Diana admitted that she was more attentive and loving to her youngest son, Prince Harry.

Royal commentator Richard Kay was a close friend to the late Princess of Wales. According to him, Princess Diana would often talk affectionately about her two royal sons. However, she's more protective to Prince Harry.

Princess Diana reportedly noticed how the members of the royal family treated Prince Harry differently from Prince William. The latter is the second-in-line to the throne while the Duke of Sussex is the sixth successor. So, she decided to give more love and attention to Prince Harry.

"As compensation, Diana poured more love and attention into Harry," Kay wrote.

"I have to. Charles and I worked so hard to ensure both boys receive equal amounts of our time and love, but others in the family seem to concentrate on William," Princess Diana told Kay.

Princess Diana also revealed that she had a row with the Queen Mother for favoring Prince William over Prince Harry.

"One day she told me how matters had come to a head with the Queen Mother," Kay continued. "Harry had complained that whenever he and William visited their great-grandmother at Clarence House, it was always William she made a fuss over and who sat next to her. 'It's not fair,' Harry told his mother."

In an interview in 1985, Princess Diana revealed that 3-year-old Prince William was a typical child his age. However, she praised her son for having a will of his own.

"He is not at all shy and he is very polite, extraordinarily enough. William is a very independent child," Princess Diana said.

Princess Diana believes that Prince William's independence could be due to his company as he is surrounded by grownups. On the other hand, she found Prince Harry to be a "different character altogether."

Although it sounds as if Princess Diana has a favoritism between her two sons, she also made sure that she would do something big for her eldest son. The People's Princess admitted that she tried to alter the monarchy system for Prince William.

"I am altering it for him, William, but in a subtle way," Princess Diana said. "Through William learning what I do and his father, to a certain extent, he has got an insight of what's coming his way."