This document discusses temperament and attachment in infants and young children. It describes three main temperament types - easy, difficult, and slow to warm up. It then discusses early social behaviors and milestones in social development from 2 months to 3 years old. The document also summarizes Harry Harlow's experiment on attachment in rhesus monkeys and John Bowlby's attachment theory. It explains Mary Ainsworth's Strange Situation experiment and the four attachment styles it identified - secure, avoidant, ambivalent, and disorganized.