Hello Mick,
I guess you have this lot, but worth a post?
Charlotte in 1891, is daughter of David and Sarah , aged 34 and 28.
In 1871, David is aged 14 and son of John Crabb, living in Doddinghurst. He shows up in the 1861 census as born 1856, which sounds good. son of John and sibling Ellen.
There is a John in the 1841 census, aged 20, and born in Doddinghurst. This could be the correct John, as he is shown as being born in 1821, but then 1841 census years are rounded down.
Anyway, what is your question?
Best
Kevan