In this 2009 photo provided by the Kowalik family, stem cell recipient Jacob Kowalik smiles on his uncle's sailboat in Chicago's Burnham Harbor. Marshal Davis, 31, added his name to a bone marrow ... more 
In this 2009 photo provided by the Kowalik family, stem cell recipient Jacob Kowalik smiles on his uncle's sailboat in Chicago's Burnham Harbor. Marshal Davis, 31, added his name to a bone marrow registry over a decade ago when he was a student at the University of Florida. He got the call to be a donor in 2009 when he was told he was nearly a perfect match with Kowalik. Doctors said abnormalities in Jacob's marrow would eventually develop into acute leukemia without the transplant. less 
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Associated Press | Photo By Kowalik Family
Sun, May 1, 2011 2:44 PM EDT