Hermanus de Leeuwe got married in Rotterdam in 1941. His wife survived the war. Also his parents survived, though his mother, Saartje van Straten, died only days after the liberation.
Amsterdam Municipal Archives; record card of Hemanus de Leeuwe
In addition, a Jokos file (number 001812) on this family is at the Amsterdam Municipal Archive. Access is subject to authorization from the Stichting Joods Maatschappelijk Werk.