It appears that Andrzej Jr. was born while his father Benedykt Wiszowaty was a Unitarian minister in Kosinowo, in the Duchy of Prussia.
Following the involvement of Andrzej Wiszowaty Sr. and Benedykt Wiszowaty in the Bibliotheca fratrum Polonorum, Benedykt's son Andrzej Wiszowaty Jr., great-great-grandson of Fausto Sozzini, taught in the John Sigismund Unitarian Academy 1726-1740, in the years leading to the drafting of the Summa Universae Theologiae Christianae secundum Unitarios (recognised by Joseph II in 1787).