“It’s one thing as a parent to watch your own children grow,” Dean David Kessler told the crowd gathered outside the Congress Avenue Building on March 21, “but I must say, as dean, it is quite another to watch this baby grow.” The dean thanked city and community leaders and iron workers, who gathered with faculty members, students, alumni and project staff as the workers lifted the highest piece of structural steel in the 450,000-square-foot building’s massive frame into place. An American flag and an evergreen tree were welded to the 1,000-pound beam for good luck, and iron workers and others signed the beam, right, before it shot skyward at the end of a crane. All told, 7,000 pieces of steel weighing 3,500 tons went into the framing, which was completed during the course of several exceptionally snowy months. “It seemed like the winter didn’t want us to finish this job,” said Otto Del Medico, the superintendent of Iron Workers Local 424. “We fought the weather every day.” When completed in March 2003, the building will house disease-oriented research programs, greatly expanded teaching space, a magnetic resonance center and an animal care facility.