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When Aiden, who has kidney cancer, said he didn't need a wig, Libby decided to donate 11 inches of her hair to the Little Princess Trust charity, according to ABC News. The organization provides wigs to children who need them.

Aiden and his family were moved by the gesture.

"She's been a really great friend and a really brave girl to cut off all that hair for him," Aiden's mother, Clare Selleck, told ABC News. "She looks beautiful."

Libby is also raising money to throw an "End of Chemo" party for Aiden, whose final chemotherapy treatment is scheduled for Dec. 30. For more information, visit the Libby's Locks for Aiden crowdfunding page or Facebook group.