The Washington Post: Children develop self-esteem by age 5, much earlier than previously thought, according to new research that suggests children gain either a positive or negative view of themselves before they begin formal schooling.

https://www.washingtonpost.com/local/education/by-age-5-children-have-a-sense-of-self-esteem-that-rivals-adults-study-says/2015/11/06/72e39f2a-83f7-11e5-9afb-0c971f713d0c_story.html?utm_term=.7ce45e463a21