DR. OZ
'(<a href="http://www.j-archive.com/media/2009-09-25_DJ_15.jpg" target="_blank">Dr. Oz delivers the clue.</a>)  Perhaps because you need a stronger immune response as a kid, <a href="http://www.j-archive.com/media/2009-09-25_DJ_15a.jpg" target="_blank">this</a> gland, in which T cells mature, is the size of a heart in infants & shrinks as you age'
the thymus