October 11 marked the United Nations International Day of the Girl, a movement for gender equality and activism. And to celebrate, a local group did something unique: writing dozens of thoughtful and heartfelt letters encouraging girls around the world.

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Dozens of people gathered at the Lemon Collective in Northwest, DC on Wednesday night, each writing handfuls of letters to different girls.

The event was organized by the Tap In Society, a local group built on the momentum of the Women's March with the goal to create positive political change. They partnered with the Letter Project, a nonprofit that works to write letters to girls who are struggling in their life.

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Some of the letters were for girls that were nominated by their families and friends while other girls nominated themselves.

"Some of the girls struggle with eating disorders or have depression. Some of them have started a new job and are overwhelmed. So, our letters are hopefully an encouragement to them," said Maria Davis, Founder of the Tap In Society.