Have found out what happened to the Skipper family and why you can't find on census after 1851, plus no death entries.
William, Charlotte, 2 daughters, plus son William, wife Hannah and 3 children, emigrated to the US!
William junior arrived in New York 25/9/1852, William senior arrived 27/12/1852 - so clearly they had gone ahead first.
On 23/11/1853, on the ship 'Florida', the following arrived:
Charlotte Skipper 50
Eliza Skipper 19
Caroline Skipper 11
Hannah Skipper 29
Charlotte Skipper 9 (from age must have been born pre Wm/Hannah's marriage?)
Catherine Skipper 7 (born as Louisa Catherine)
William Skipper 3
However, according to the ships passenger listing, 3 of them died during the voyage i.e. Charlotte 50, Eliza 19 and William 3!
William and Hannah eventually settled in Monguagon, Wayne, Michigan but had a further child bc.1856 in New York, a daughter named Amanda/Amedea (or something like).
Of William/Charlotte's 11 children I found, this seems to be what happened to them:
Edward born 1815, died 1815
William born 1818 - married Hannah Harmer 1843, went to US 1852, died in Michigan 27/12/1889 (his wife died 17/3/1872).
Edward born 1819, died 1820
Mary born 1820 - think she married a John Howard 11/9/1843 Thorpe St. Andrew, father shown as William Skipper, Bricklayer. Cannot find in census after marriage.
Rebecca born c.1822 - married Thomas Page 1842. Cannot find after marriage.
Ann born 1823 - married William Brunson 1848 - she and family remained in UK
Lewis Myhill - married Ann Bird 1848 but he died in 1850.
Robert - born 1827, died 1852.
John born 1829 - was a Tailor but cannot find after 1851 and didn't appear to go to US with rest of family.
Elizabeth born 1833 - married John Pearson 1849. Cannot find after marriage.
Jane Caroline born 1840 - went with family to US.
By 1861 - William junior has settled in Michigan as I mentioned above.
William senior is, I think, in Canada in 1861 - found a William Skipper, widower, aged 70, Bricklayer, living alone in West Gwillembury, Simcoe, Canada West.
Haven't actually searched but wondering whether the married daughters (with exception of Ann who remained here) and their families also went to the US since I can't find them in UK records.
Nor can I find out what happened to their son, John born 1829, a tailor, after 1851.
Annette