look at the words/phrases used the describe the small children and the twins.how have these changed as the book has pregressed ? why is this significant ?

This is interesting. The "Littluns" are grouped into one group with similar characteristics. The twins are seen as one person but by the end of the novel we begin to see more of the individual Sam and Eric. The Littluns, with the exception of a few (Percival and Henry), become savages with extended bellies.

Stay focused Benjamin.