In 1841 James, age 40, a carpenter, is in Brighton with Mary 40, Alfred 12, Henry 9, Sarah 6.
In 1851 he is age 51 born Keymer, with Jane 39 b Ditchling and Amy? King step daughter and Mary King step daughter. Both seem to be age 8 but it is not very clear. Still in Brighton.
I would be very wary of the trees on Ancestry. They seem to be totally wrong with some information. I misread the Henry on 1841 as Mary at first too until I noticed his age was in the male column. They have a marriage to Mary Gent far earlier than the possible one that shows on freebmd in 1845 - though there is no proof she is the bride, nor that it is the correct James.
However, there is a marriage to Jane King and as he is with a wife called Jane in 1851 and step daughters called King the freebmd marriage in that year does seem very likely. Brighton 7 347 Mar 1851.
Brighton covers a large area though so not knowing the church hinders us in looking at parish registers.
Making progress though.
Andrea