Two-year-old children are at a difficult age; and as a result, they're often prone toward a tendency to get frustrated and have a "temper tantrum".  Because tantrums are so often associated with this particular stage of development there can be no real guarantees that any particular approach will always work.  Still, the author of this article got through her own three children's third year without any of them having any tantrums (and she's kind of proud of that).    With one of those children being an adopted child,  and with all three of those children being very active, "busy", little folks; it's unlikely that the tantrum-free two-year-olds "just inherited a calm disposition".

There's no magic to having tantrum-free or almost tantrum-free two-year-olds.    Parents need to understand the "issues" of that third year of life.  They also need just a little extra patience and willingness to take a few extra steps to prevent some frustrations for their child.  The good news is, however, that children are two years old for only a year; so taking a few extra steps to reduce their frustrations can make life a lot more pleasant for all involved.