five-year-old corey edwards often asked why his parents were not married .
craig and jemma had put their wedding on hold to fight his heart defect .
they decided to tie the knot when they discovered his illness was terminal .
the edwards made history as the first couple to get married in the hospital .
it required special written permission from the archbishop of canterbury .
they fulfilled corey 's dying wish by organising ceremony within 48 hours .
he held the rings , while staff made a cake and the decorated hospital ward .