Jacob van Os was born on 22 February 1876 in Amsterdam. He was born to hat-maker Meijer van Os and Sipora Content, whom themselves were both born and raised in Amsterdam.
Jacob was the second oldest child, born three years after his parents 1873 marriage. His older brother Levie was born in July 1874. Jacob’s sister Caroline was born almost a year-to-the day after him in 1877.
The family at the t…