the eldest of sisters and brothers—a head of a gang or a bandit chieftain
老大
old;eldest child;number one in order of seniority 少小离家～回，乡音无改鬓毛衰。(贺知章《回乡偶书两首》)I left home young.I return old,speaking as then,but with hair grown thin.(Impromptu Lines Composed upon Returning to My Native Place by He Zhizhang.)