They were obviously doing OK in 1851 - employing 40 men at the business.
I havent pinpointed the family yet in 1861 (there is a Wm and Maria,but they have different places of birth and are a carter and a charwoman, so unless they have fallen on very hard times it doesnt look likely)
but I think this is the youngest child Henry (age 13 bn Maidstone)
RG9 525 80 10
Boughton under Blean Boarding School
and eldest son also William James is at
RG9 512 80 12 age 21 married to an Elizabeth, living in Ashford, and a nurseryman like his dad.