Like James Stewart , Cagney became so familiar to the public that they usually referred to him as `` Jimmy '' Cagney . They adopted a son , James Cagney , Jr. in 1941 , and then a daughter , Cathleen `` Casey '' Cagney . Cagney was a very private man , and while he was more than willing to give the press photographs when necessary , he generally spent his private time out of the public eye .