Her father was William Kingdom, a contracting agent for the Royal Navy and the army, and her mother was Joan Spry.
[2] While working there as a governess she met Marc Isambard Brunel (1769–1849) at Rouen in the early 1790s.
In 1793, Marc Brunel had to flee the French Revolution, going to the United States, but Sophia remained in Rouen.
[3] Marc Brunel remained in the United States for six years, sailing for England in February 1799.
They had two daughters, Sophia Macnamara and Emma, followed by a son, Isambard Kingdom Brunel, born on 9 April 1806.