11When the 1 is the parent
As a parent, a 1 sets the standard and expects it met: encouraging when you try, impatient when you do not. Children of a 1 learn independence early and need to hear that they are loved for who they are, not what they achieve.
As a child, a 1 wants to do it themselves, from shoelaces to career. Praise the effort, hold the line on the few rules that matter, and let the rest be theirs.