Angelina Jolie Reveals in Powerful Essay that Two of Her Daughters Had Surgery

Angelina Jolie is opening up about health issues faced by her children.

On Sunday, the actress, 44, revealed in a first-person essay in Time that two of her daughters have had recent “medical challenges” that resulted in surgery.

The essay, “Why Girls Deserve Love and Respect on International Women’s Day,” begins with her sharing her family’s recent health issues: “I have spent the last two months in and out of surgeries with my eldest daughter, and days ago watched her younger sister go under the knife for a hip surgery,” wrote Jolie.

“They know that I am writing this, because I respect their privacy and we discussed it together and they encouraged me to write,” she added. “They understand that going through medical challenges and fighting to survive and heal is something to be proud of.”

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David Fisher/Shutterstock Vivienne Jolie-Pitt, Angelina Jolie, Zahara Jolie-Pitt and Shiloh Jolie-Pitt

While the Maleficent actress referred directly to 15-year-old Zahara, she didn’t specify which of her two younger daughters underwent hip surgery. However, PEOPLE has confirmed that, Shiloh, 13, was photographed walking on crutches over the weekend while out shopping with her mom and sister, Vivienne, 11.

Zahara was also seen stepping out after her surgeries, attending Cirque du Soleil with her family, where she was seen wearing an IV drip.

A source from the hospital tells PEOPLE that Jolie has been by her kids’ side for the past two months as they were in and out of the hospital.

“She’s been in her pajamas, in the pediatric ward, by their side,” the source says.

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Another source says Jolie took Shiloh and Vivienne shopping for flowers on Sunday. “They all got flower arrangements. Shiloh looked like she was used to walking with the crutches. She was pretty quick and didn’t struggle. She only needed some help getting into the car. Vivienne was sweet and kept an eye on her. You could tell that the sister are close and care about each other.”

In her essay, Jolie went on to describe the sweet way all three of her daughters stepped up to care for one another amid the surgeries.

“I have watched my daughters care for one another. My youngest daughter studied the nurses with her sister, and then assisted the next time,” she wrote. “I saw how all my girls so easily stopped everything and put each other first, and felt the joy of being of service to those they love.”

Monica Schipper/Getty

She then praised her girls for their strength and for facing the challenges head-on.

“I also watched them face their fears with a resolute bravery,” Jolie added. “We all know that moment when no one else can help us, and all we can do is close our eyes and breathe. When only we can take the next step or breath [sic] through the pain, so we steady ourselves and do it.”

The Salt star also gave her three boys — Maddox, 18, Pax, 16, and Knox, 11 — a special shout-out, writing that they’ve also helped look after their sisters and that they have been “supportive and sweet.”

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Another source tells PEOPLE that the girls are now on the mend. “They look to be recovering,” the insider says.

Jolie shared the news as a social commentary for International Women’s Day, imploring readers to “value girls” while emphasizing that their “softness, their openness and instinct to nurture and help others, must be appreciated and not abused.”

“My wish on this day is that we value girls. Care for them. And know that the stronger they grow, the healthier they will be and the more they will give back to their family and community,” she concluded her essay.

Jolie shares her six children with ex-husband Brad Pitt. The couple split after two years of marriage and 12 years together.