I can see a James Lambert, age 25, occupation Ag Lab, with a Mary Lambert, age 25 and Mary Lambert, age 1. Address is Mill Corner, Leiston Blything.
A Mary Ann Lambert's birth was registered Mar Qtr 1840, Blything - mother Sheppard. A Henry James Lambert was registered Jun Qtr 1852, Blything - mother Sheppard.
Think James appears as a Carter in subsequent Censuses - in 1891, age 78, "living on own means".
Do you have a Census reference for "James Lambert, miller" living at "Mill House"?