Mary’s brothers included John and Joseph Mawbey who owned a successful vinegar distilling business.
Subsequently he was promoted to Chief Clerk (1798-99), a position reporting under the Joint Secretary and with a general advisory role to the Board of Treasury.
He provided evidence to the Committee on American Claimants Petition in February 1812 where he confirmed the payment of awards under the 7th Article [3] of the Treaty of Amity (The Jay Treaty) between the United States and Great Britain in 1794 and the subsequent Convention that was ratified between the United States and Great Britain in 1802.
In 1819 Joseph Junior was also appointed as Superintendent of Returns to Parliament for the Treasury Office, a position he also held in 1820.
Their sons included Joseph, who served as a junior clerk in the treasury, but died in 1822, John and Thomas Alcock (MP) who became an MP and who inherited the Kingswood Warren estate from a paternal uncle, a lawyer also called John Alcock.