One of Frank Hills' brothers was Thomas - it might be assumed he was the eldest and named after his father, but this may not be so. He had been born in Lyme Regis in 1804. His early work is not known. In 1833 he patented a boiler grate and gave his address as St.Michael's Alley, Cornhill - perhaps the address of Robert Hills' City office. Thirteen years later he was looking for a job and in 1846 he applied for the post of Deputy Superintendent at the Phoenix Gas Works in Greenwich. He said he was 'a good practical chemist and accustomed to the control of workmen' who would want a salary of £300 a year. Phoenix turned him down because he was 'too experienced'. After that he worked for Frank - 'dealing with the commercial business at the works' both at Deptford and East Greenwich. In the early 1870s he joined Frank on the Board of Thames Ironworks. As an old man he lived at 8 The Grove on Blackheath with his second wife and their young son. This son, Thomas Herbert, described in 1891 as a 'student of chemistry' seems to have inherited the Deptford Chemical Works. His family of four daughters - the eldest in her mid-thirties - still lived with him in the 1880s.83 He died in 1885.
Frank also had a brother George, about whom little has been discovered - no will and no address. He seems to have worked for Frank at Deptford. He held joint patents with Frank on the manufacture of both sulphuric acid and sugar. On both patents the address is given as the 'Deptford Chemical Works'. George seems to have been active in dealing with these patents, because the record says that he 'swore it in Chancery'. Does this mean that George was a sugar manufacturer? It was a very common business in London in the last century and in very different to other chemicals in the manufacturing process involved. In the 1820s some inventors, like Daniel Wilson, developed equipment for heating inflammable liquids that were useful for both tar and sugar. We have already noted that Frank's ammonia products were specially aimed at the West Indian sugar plantations. George was still alive when Frank made his will in 1890. He did not leave money to George, as he did to his other brothers and sons but left instead a sum to be used 'for his benefit'. That seems to imply that George was not able to make his own decisions and perhaps he needed to be looked after.
Arthur Hills has remained elusive despite indications that he was very important family member. He gave his address as 'Norwood' when he witnessed Frank's marriage agreement in 1847. It may be that he managed the chemical works, which the family owned at Nine Elms and, perhaps, another in Wandsworth. No will has been found for Arthur, and no definite census information. He could be the Arthur Hills of 18 Bedford Row, Clapham in 1851 - an address on the same social level as Thomas Hills' house in the Grove. This Arthur Hills was born in 1803, making him older than Thomas. He is described as a 'wholesale drug merchant'. Arthur had a chemical works on the Isle of Dogs in the 1850s called, significantly, 'Anglesey' Works.' This was a sulphuric acid and colour works at Millwall immediately across the river from East Greenwich. It was an in an area known as 'Folly Wall' where, in the 1990s, housing is being built. He also rented a plot of land at Deptford Creek next to the Deptford Chemical Works for nearly 30 years - did the brothers arrange things so that each held small parcels of land on which their works stood. He must have died in 1891 - since he was alive when Frank made his will in 1890, but dead by the time Frank's death in 1892.