annabelle cox was born at just 20 weeks in canberra on may 5 last year .
parents jaye and matthew made decision to give birth prematurely after scans showed she had developed serious form of spina bifida .
they contacted angel gowns after making heartbreaking decision so jaye 's wedding dress could be redesigned .
charity turns donated wedding dresses into outfits for babies .
annabelle was born weighing just 290 grams and survived for five minutes .