The absolute known people are William Stanbrook b1798 Longparish, Hampshire and Stephen Stanbrook b1826 Longparish, Hampshire. This comes from census records.
I have the marriage record for Stephen to Mary Weekly in 1852 in Harmondsworth, Middlesex which gives his father's name as Stephen a labourer.
There is a submitted record for the christening of William Stanbrook on familysearch which gives his parents as Stephen and Mary.
William married Elizabeth Mary and a submitted record on familysearch gives the date as 12/10/1826 and Elizabeth's maiden name as Whyatt. William and Elizabeth had a son Thomas b1828 in Colnbrook, Buckinghamshire and a daughter Elizabeth b1831 in Langley, Buckinghamshire.
Stephen worked on the railways in London. Thomas went to New Zealand and after having failed as a miner ran a number of hotels. He finally returned to Engalnd in around 1897 and ran the Five Bells in Harmondsworth. Elizabeth it seems never married and died in 1856 in Islington. The reason Thomas returned from New Zealand was "... to receive a large fortune left him by a wealthy relative lately deceased." There is no proof but this MAY have been his sister.
William was the tax assesor in Harmondsworth.