Original sentence: Robert Pearson Brereton (4 April 1818 – 1 September 1894), joined Isambard Kingdom Brunel in 1836, aged 18, and became his chief assistant in 1844, aged 26
Edited sentence: Robert Pearson Brereton (4 April 1818 – 1 September 1894) joined Isambard Kingdom Brunel in 1836, aged 18, and became his chief assistant in 1844, aged 26