LOS ANGELES (CBSLA.com) — He’s only 6, but Dylan Siegel recently wrote a book to help raise money for a friend and classmate named Jonah, who is battling a rare liver condition called Glycogen Storage disease.

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One in a million get the disease. It’s truly rare. Then again, 6-year-old authors are pretty rare, too.

The book is called “Chocolate Bar” and Dylan is hoping to raise $1 million towards a cure. He’s at $20,000 well on his way.

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Dylan and Jonah will be at Barnes & Noble at the Grove this Sunday (December 16th at 2 p.m.) for Dylan’s first public book reading and fundraising event.

There will be music from their school choir, a book signing and arts & crafts.

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You can also help support the cause by clicking here.