David Alter was deported to Sobibor in June 1943 from Vught via Westerbork on the so-called children's transport. He was 3 when he died. J. de Moei, Joodse kinderen in het kamp Vught (Vught 1999) 13
In addition, a Jokos file (number 10129) on this family is at the Amsterdam Municipal Archive. Access is subject to authorization from the Stichting Joods Maatschappelijk Werk.