Isaac Speelman was a son of Koopman Speelman (sometimes called Karel) and Judith Kan. He was born on 10 November 1891 in Amsterdam and had an elder brother Jacob Abraham from 1890 and two sisters, Elizabeth from 1893 and Saartje from 1899. His mother however passed away already in 1912 and his father remarried on 12 July 1916 in Zaandam Rebecca Lopes Quiros, a daughter of David Lopes-Quiros and Sa…