Eliza Tween's vitals match those of Margaret's daughter seen in the 1851 census.
So poor Margaret was widowed agin between 1863 and 1871 ...
Heres Eliza's marriage to William Tween
Marriages Sep 1860 Nunn Eliza Dunmow Vol 4a Page 477
Tween William do do do
Which begs the question - why - if the 17 year old Henry Eaton is described as 'wife's son' in 1871, did she not marry as Eaton

He is with the newly-weds in 1861 ..... but shown as a son.