Mariano was the son of Roberto D'Angelo and Orsolina unknown. The date and place of his birth have not been found.
His wife was Maria Demarinis, who he married in ABT 1960. The place has not been found. Their five known children were Boy 1 (?-?), Girl 1 (?-?), girl 2 (?-?), Girl 3 (?-?) and Girl 4 (?-?).