Izaak Wallega was a son of Meijer Wallega and Rozette Schnitseler. He married Sientje Hakker in Amsterdam on 7 February 1940, a daughter of Abraham Hakker and Bloeme Walvisch.
City Archive of Amsterdam, archive cards of Meijer Wallega and Sientje Hakker .
In addition, a Jokos file (number 6685) on this family is at the Amsterdam Municipal Archive. Access is subject to authorization from the Stichting Joods Maatschappelijk Werk.