Son of Theodore Lambert and first murder suspect.
In original The Case of the Chemical Syndicate story he was just young Lambert and the first one who found his dying father in the library.
In Mike Friedrich version he was given first name Mel and was presented as a young anti-industrial & anti-system hippie. He was also the first one who found his father dead. Robin suspected him of murder all the way because of his views. It turned out that the hired killer was only posing as Mel to draw suspicion on him.
In Marv Wolfman’s version he’s name was Ted Lambert he was suspected of murdering his father because of his ecological views on pollution that caused his father’s plant.
In Alan Grant’s version he’s again Mel Lambert and the first one to find his father dead at the plant. This time he was also a small drug dealer that was receiving cocaine packs from Mexico via company’s transport. His father found out about this procedure and they argued so that raised suspicion of murder on Mel but it was quickly dismissed by Batman.