I've just been through the fiche for Westleton again - William Rous' wife was definitely Catherine. Their marriage is recorded in the PR so clearly and in a good hand that it's impossible to mistake it for anything else. At their marriage 16 August 1774 Catherine's surname is written as Calver, but at the baptism of Letitia it could be Carver.
William and Catherine had three known children - Elizabeth baptised 1778, Richard baptised 1783 and Letitia baptised 1787, all at Westleton. This William Rous (seen in the PR's with and without the 'e') is a puzzle, he cannot belong to Thomas who married Hannah as their son William was baptised in 1759 and married Sarah Wink at Laxfield in 1783. Also William s/o Thomas and Hannah would have been too young to marry in 1774, well maybe not too young but it would be highly unlikely.
I've never found another marriage for William after the death of Catherine in 1808.
Lettice Rous baptised at Benhall in 1786 the daughter of John Rous and Mary (Crow) it was this Lettice who married Thomas Rous (son of Thomas Rous and Sarah Day) in 1809. In the census of 1841 Lettice was staying with her daughter Athelinda (who married William Nollar) at Middleton, Then at the next census in 1851 Lettice (by then a widow) was living at Benhall with a Sarah Rous aged 91. Also there were two grandchildren of Lettice Rous - Louisa Nollar and Margaret Rous (daughter of Lettice's son James). Lettice is described as being 'housekeeper', and as I said previously it suddenly struck me that Sarah Rous wasn't her mother in law, but her step mother, the second wife (previously Sarah Goose) of her father John Rous. Lettice also gives she was born at Benhall. I should add that Sarah Goose, the second wife of John Rous was mentioned in his will, stating that she was to have rooms in their house at Benhall, any household 'bits and pieces' she wanted and an income paid every quarter!
Having spent many hours poring over the PR's for Westleton it appears there must have been two Rouse families - or at least two (or more) branches of the same family.............I have never been able to get my head around where (for instance) William Rous and Catherine fit in, or other Rous people that don't appear to connect to the Rouses I'm familiar with. I have all the wills that should connect these people, and they don't!