Through his maternal Grandmother, Liese Bronfenbrenner, née Price, Soll is the great grandson of the English author and professor, Hereward Thimbleby Price, and a descendent of the Prym family of industrialists and academics from Aachen, Stolberg, Düren and Bonn, Germany.
Friedrich Emil Fritz Prym (28 September 1841 Düren; 15 December 1915 Bonn) was a German mathematician who introduced Prym varieties and Prym differentials.