Kate Middleton 'Doesn’t Worry' About Her Children's Behavior 'Too Much': 'She Loves to See Them Being Kids'

Over the years, Kate Middleton and Prince William's three kids, Prince George, Princess Charlotte and Prince Louis, have been known to show off their cheeky behavior at royal events. However, the princess, 42, who is currently battling cancer, doesn't seem to mind.

"Louis is an energetic child and clearly was unable to contain his excitement at being at a public event,” said a source while talking about the June 15 Trooping the Colour event, where he made several funny faces. “Kate doesn’t worry about their behavior too much. She loves to see them being kids."

Meanwhile, Charlotte "is a doting big sister," the insider noted. “She keeps Louis in line when needed. She’s very proper about these things.”

Kate made an appearance at the event alongside her husband and kids. However, an insider said she "wasn't her usually energetic self, and she seemed mindful of the amount of energy she could expend."

"But her smiles were genuine and gave people hope for her full recovery," they added.

As OK! previously reported, Kate spoke out one day before she made her return to the spotlight.

"I have been blown away by all the kind messages of support and encouragement over the last couple of months. It really has made the world of difference to William and me and has helped us both through some of the harder times. I am making good progress, but as anyone going through chemotherapy will know, there are good days and bad days. On those bad days you feel weak, tired and you have to give in to your body resting. But on the good days, when you feel stronger, you want to make the most of feeling well. My treatment is ongoing and will be for a few more months," the princess wrote via Instagram on Friday, June 14.

"On the days I feel well enough, it is a joy to engage with school life, spend personal time on the things that give me energy and positivity, as well as starting to do a little work from home," she continued.

Kate then shared more details about her recovery. "I’m looking forward to attending The King’s Birthday Parade this weekend with my family and hope to join a few public engagements over the summer, but equally knowing I am not out of the woods yet," she said. "I am learning how to be patient, especially with uncertainty. Taking each day as it comes, listening to my body, and allowing myself to take this much needed time to heal. Thank you so much for your continued understanding, and to all of you who have so bravely shared your stories with me."

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It's unclear when Kate will make her next appearance, as the royal family is determined to keep "tight-lipped" to avoid any leaks, an insider revealed.

"The reality is nobody really knows how Kate is," royal expert Ian Pelham Turner claimed to Fox News Digital. "There are many whispers by those who wish to further their careers. But in reality, when the royal family wishes to close the doors on the world, they have had centuries of practice in the art."