I've no idea whether anyone who posted to this thread is still following it, and if so whether they remain interested in the family. But I thought I'd send a short follow-up in case.
Joseph HATTO, mentioned earlier in this thread, was my great great grandfather. According to his birth certificate, he was born at 3pm on 22 Sept 1840 in Chilton, son of William HATTO and Martha HATTO née KING. William and Martha's marriage at Chilton on 29 Jul 1840 has already been reported, as has Martha's baptism at Chilton on 24 Oct 1824, daughter of William and Ann KING. These five (Joseph, William and Martha HATTO, and William and Ann KING) are living together on the 1841 census.
But then Ann KING died (bur 4 Apr 1843 at Chilton, aged 50), followed by William HATTO (buried 30 Jun 1850 at Chilton, aged 31). William KING remarried at Chilton on 27 Dec 1849 to a Janet FORTUNE (from Berwickshire according to the 1851 census). This marriage record tells us William KING's father was also named William KING, and the 1851 census says he was from Chilton, but the OFHS transcript has no suitable baptism. On the 1851 census, Joseph was in the union workhouse at Wantage. Martha was living by herself in Chilton, however the following year on 18 May 1852, Martha gave birth to an illegitimate daughter in the union workhouse; this daughter died there on 10 Jun 1852 seemingly never having been named.
Martha HATTO remarried at Chilton on 5 Aug 1861 to Thomas WETHERALL, son of William WETHERALL. Thomas had been baptised 26 May 1839, his parents given as William Collins and Elizabeth WITHERELL. (Collins is a middle name.) Martha was buried at Chilton on 20 Dec 1899, aged 75. I'm not aware that Thomas and Martha had any children, and none are listed on the 1871 or 1881 census.
William HATTO must have been born about 1819 based on him being 21 when he married in 1840 and 31 when he died in 1850. According to his marriage record, he was from Chilton and his father was also named William HATTO. In fact, five children of William HATTO were married at Chilton between 1838 and 1841, and four of them correspond to baptisms in the Chilton register for children of William and Sarah. However there is no baptism of a William in around 1819, nor is there any record of William and Sarah having a son baptised named William, though there is a gap in their children's baptisms between 1817 and 1823. The parish register and census both suggest there was only one William in Chilton of a suitable age to be father of a child in 1819, so I think it almost certain therefore that Martha's husband William is a child of William and Sarah HATTO. Maybe he was baptised elsewhere, or was baptised there but the clerk forgot to write it up; or maybe even they forgot to have him baptised.