LONDON -- Since their first meeting nearly 15 years ago998 Archives author J.K. Rowling and actress Emma Watson seem to have formed a lasting friendship.

Although both of these extraordinary women undoubtedly lead very busy lives, they still find ways to support one another -- even if it's just a simple tweet.

Most recently, 26-year-old Watson shared a photo of herself wearing an official "Be the Light" T-shirt in support of Rowling's charity, Lumos.

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The shirt features a quote from Rowling's speech at the 2008 Harvard University commencement ceremony: "We do not need magic to transform our world; we carry all the power we need inside ourselves already."

At least 60 percent of proceeds from the sale of the T-shirts will go towards supporting the organisation's work to help provide care for, and end the institutionalisation of, children.

To learn more about the work Lumos does in support of vulnerable children, click here; to purchase one of the T-shirts (which will begin shipping on Oct. 19), click here.