Angelina Jolie made a surprise donation to two 6-year-old boys in London who have been running a lemonade stand to raise money for the humanitarian crisis in Yemen.

The actress sent an “extremely generous donation” to the pair of best friends last week, accompanied by a letter which said “Dear Ayaan and Mikaeel, Thank you for what you and your friends are doing to help children in Yemen,” Jolie wrote in a signed note to Ayaan Moosa and Mikaeel Ishaaq. “I’m sorry I’m not able to buy a lemonade from you, but I’d still like to make a donation to your stand.”

In a cute video, the boys thanked Jolie. “Just wanted to say thank you for donating to our cause,” one of the boys, Ayaan Moosa, said. “It’s really helped us raise more money and awareness for Yemen.” They promised the actress that they’d have a glass of lemonade ready for her the next time she visits London, and according to a People source, Jolie plans to meet the boys when she’s next in the United Kingdom.

The post does not say how much money Jolie donated, but, in all, the boys have reportedly raised more than £60,000 (or more than $76,000) for Yemen. The money they raise is sent to One Nation U.K., which sends food, water and medical aid to those in need in Yemen. You can find the Lemonaid Boys’ donation page here.

The country has struggled with ongoing war and conflicts since 2015, when the Yemeni Civil War began. The United Nations Office for the Coordination of Humanitarian Affairs reported that an estimated 24 million people are in need of assistance in Yemen, including 12 million children.

“They have nothing, like, the things you need to survive. They have no water, food, oil. And we have all of those things and that’s why we help them,” Moosa told NBC News.