Age differences in development and mixed age grouping in early childhood education

In this essay, consider characteristics of development in two different time periods: 1-2 years and 4-5 years. The essay requires to demonstrate an understanding of the differences in development between toddlers and pre-school aged children, and to discuss the advantages and disadvantages of mixed age groups in early childhood education. The discussion should draw on a variety of sources from review to research articles. Literature used should be from high quality peer reviewed sources(journals, books, government websites, etc.) Literature should be up-to-date, not more than 10 years.
Can I request my writer to be from Canada, US or UK.Thanks.