Child Dev By indie.gee Apr 18, 2016 18 months Says 'no' a lot -Gets frustrated a lot Angry since he/she can't perform certain tasks -Self-centered Oct 18, 2016 2 1/2 years Tense, insecure, easily frustrated Apr 18, 2017 3 year olds Stubborn, independent Oct 18, 2017 3 1/2 year olds Disobedient, easily upset