Over 50 Boston-area parents converged on Downtown Crossing Friday to show just how much wearing their children lets them do - a choreographed song and dance routine. Sponsored by Boston Babywearers (BBW) and Boba Inc., designers and manufacturers of premium baby carriers and accessories for babywearing parents, the group included children ranging from newborn to 3 years old being worn in soft-structured Boba Carriers and Boba Wrap stretchy baby wraps. Older children were even visible wearing their dolls in