Toddlers have minds of their own and strong feelings that they express with gusto. “No!” becomes a favorite word and a powerful way to assert their independence. Learn ways to help your toddler learn self-control from 12-24 months at https://www.zerotothree.org/resources/1287-developing-self-control-from-12-24-months
For 10 family ideas for calming a toddler tantrum, take a look at http://wellroundedny.com/handle-toddler-tantrum/