Ah! If you search on
www.freereg.org.uk choosing baptisms, Essex, St Osyth, you'll find the baptisms for Robert and Hannah's children:
06 May 1810 Hannah
08 Oct 1814 James (surname is spelt "Balls" but probably "Beales")
19 Oct 1820 Eliza (born 17 Aug 1820)
16 Jan 1825 Rebecca
16 Sep 1827 Benjamin & Elizabeth (both buried a month later)
Robert was buried on 06 Dec 1854 in St Osyth, aged 77.
Is this Robert Beales the same Robert who's in St Osyth in 1851, married to Mary Ann, with a son who's a Chelsea pensioner? (and also 1841?)
Ah... I've found a marriage in Great Bromley on 6th February 1809 between Robert Beales, bachelor of Donyland, and Hanah May (of Gt Bromley, marital status not given). Robert signs, Hanah marks. Witnesses both mark: Will Rolf, Sarah May. Although it says Robert is "of Donyland", it still could be your man as he may have moved around. The "of" parish isn't necessarily where he was born.