BIG

 nickname borrowed from Blues musicians (as in Big Mama Thorton, Little Richard, Memphis Slim, etc ...) 

MAX

 short for MAXENCE. Ancestors include:  
           Roman Emperor MAXENCE (280-312)  
           Edgard MAXENCE (1871-1954) Painter, Member of the Academy of Arts

LEO

 Zodiac sign, born 28 July 1957