Thomas Simpson, a cooper’s boy,  was a convict transported for a felony for 7 years on the Countess Harcourt, after time on a hulk, where he was described as friendless, behaved well.  He was a 19 year old cooper's boy, with grey eyes, brown hair, and a slightly pockpitted face, from Hexton, a village just north of Luton in Hertfordshire. He was tried at Middlesex on 13 January 1819.  

He arrived on 13 January 1819, and had a turbulent time between August 1822 and April 1827, with five charges against him for absconding or being absent from his master's place. He suffered 50 lashes twice. On 16 April 1827 he was found in the house of William McDonald with Catherine Porter, aged 14 years at half past nine o'clock last night, but was discharged. McDonald married Margaret O'Brien, Catherine's aunt, only a month earlier. The relationship must have continued, for they were married five months later, almost certainly because she was pregnant with her daughter Catherine. The marriage clearly did not last. There were no further children, and she married again in 1842, aged 29, presumably when Simpson had died.