Brayden and Trevin were diagnosed with Purine Nucleoside Phosphorylase (PNP) Deficiency. On July 5, 2007 doctors at Duke University Medical Center in Durham, North Carolina performed life-saving bone marrow transplants.

In case you're wondering exactly what PNP is, reference the sites below.

In a nutshell, cell replication is inhibited, which is essential in the functioning of one's immune system. Because cells don't replicate, the person with PNP is unable to fight infections, leaving the children extremely vulnerable to neurological issues, autoimmune disorders, and cancer.

PNP is very rare, and only a small number of cases have been documented.

The boys will be undergoing intense treatments, including chemotherapy followed by a complete bone marrow transplant.

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