She died whilst Robert was very young and he was sent to Dorset to live with his maternal uncle, though returning a few years later to Blackheath to attend Maze Hill School and then, in 1810, begin working for his father as a nurseryman.
On settling at Blackheath for employment, Halley had at first regularly walked into London each Sunday dutifully to attend the Presbyterian Chapel in Oxenden Street.
Robert began to look for a career in the dissenting chapels, and though not being successful in applying to Hoxton Academy, he was offered a place at Homerton College in 1816, under the tutorship of John Pye Smith, for a six-year course.
In the previous year he had become noted in the abolition movement, delivering a sermon on The Sinfulness of Colonial Slavery at the Meeting House of his former tutor, John Pye Smith of Hackney.
His memorial, a stone coffin tomb with hipped top, stands at Abney Park Cemetery, in Stoke Newington, London.