Sarah Theresa Brooks was born on 19 September 1850, on board the ship Harpley, at Plymouth, England, prior to sailing to Australia., She was the second child and only daughter of Henry Brooks and his wife Emily Donovan. The family migrated to Australia in January 1851 and settled in the Geelong area, where a relative Thomas Edols resided. Henry Brooks died shortly after their arrival in Australia.The Brooks family resided in Victoria until 1873, when Sarah’s brother, John moved to Western Australia, to pursue an opportunity to own land, and she and her mother followed shortly after in 1874. They lived in an isolated location and grazed sheep. John Brooks lived on Lynburn Station near Thomas River, followed by Marlburnup Station near Point Malcolm. From 1877, the family lived at Israelite Bay, near Esperance.