First: We ask UCLA history professor Katherine Benton-Cohen how America transformed from a country with open borders to one - by the 1920s - with a strict quota system.

Next: Pediatrician Nadine Burke Harris explains the science behind how childhood trauma permanently impacts children’s mental and physical health.

Then: Remember that whole “all men are created equal” thing? We investigate how the end of the 18th century brought about a new discussion of human rights - one that forever changed history.