In addition to famously taking care of her brothers, Prince George and Prince Louis, Princess Charlotte also appears to be taking care of her mother, the Princess of Wales, who is undergoing ongoing treatment for cancer.

Ingrid Sward, a royal biographer, told the Mirror that Charlotte is "protective" and "caring" for her mother, Sward said: "I think Charlotte is really taking care of her mother," said Sward, who has written numerous royal biographies and is also the editor in chief of Majesty magazine. Sward, who has written numerous royal biographies and is editor-in-chief of Majesty magazine, said, "I think Charlotte really takes care of her mother. Speaking specifically about the interaction between mother and daughter at last month's "Trooping the Colour," Sward said, "It was so cute to see her [Charlotte] standing in front of her [on the balcony of Buckingham Palace] and continuing to chat with her. Charlotte seems to adore her mother very much, and I think that's lovely too."

It is well known that Kate is close with her mother, Carole Middleton, and Sward added, "Kate and Charlotte are great friends, and I think their bond is very precious to Kate. The mother-daughter relationship is obviously especially important to Kate."

In a moment in "Trooping the Colour" when Charlotte watches over her mother, Kate and her three children are in a carriage, the Mirror wrote, when the rainy London weather that day steamed up the carriage windows and "she was unable to wave to the cheering crowd outside.

"The mother and daughter cleaned the windows so they could greet their royal fans.

At one point, however, Kate stopped wiping, but "her obedient daughter continued, cleaning the main carriage windows for the pair," the magazine reported. And when she wasn't cleaning the carriage windows, "she was also looking after her cheeky little brother, Prince Louis," the Mirror reported. On several occasions, the 9-year-old Charlotte glanced over at Prince Louis to make sure he was behaving."

After Trooping the Colour, Kate was "exhausted," a source told OK magazine. 'It had been a long day, and it seemed to have taken its toll on her.' Regarding her vulnerable social media posts on June 14, when she revealed that she would be attending the King's birthday parade the next day, the source continued, "She was very upset." She absolutely has her bad days, and that is something she has not shared in the past. Kate is not the only one battling cancer and she realizes that being honest about her battle can help others."

According to Ailsa Anderson, former press secretary to Queen Elizabeth, "She may be the Crown Princess, but she is still a mother and a wife, and like anyone in that situation, she experiences the same set of emotions, worries and fears," she said.

A source who spoke to OK added, "Her display of strength proves that she will be a fine queen one day. She is a fighter for herself, her family, and her country."