a ceremony was held on boylston street on tuesday morning to mark two years since the april 15 , 2013 bombings .
the family of eight-year-old martin richard , the youngest victim to lose his life , helped unveil commemorative banners at the site .
jeff bauman , who lost both his legs , also walked along the street on his prosthetic legs with his wife erin and their baby daughter nora .
he also greeted carlos arredondo , who helped save his life .
a moment of silence was also held at 2.49 pm to mark the first of the explosions , which killed three people and left more than 260 injured .