5-year-old Seth Lane is battling Severe Combined Immune Deficiency (SCID) which doctors say lowered his immunity so much he "lives in a bubble".
His mother says Seth is being considered for a second bone marrow transplant in order to save his life.
In a Youtube video which is now going viral, Seth is seen on his hospital bed holding up cards which tell his heartbreaking story and urge people to wear yellow on March 27, 2015.
To find out more about Seth and his cause CLICK HERE
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