Your annoyingly picky child that turns down everything but plain noodles and 400ct Egyptian cotton sheets becomes "selective."
That stubborn streak that makes you want to throw your child into the back of your SUV and drive them to the nearest Dog Pound for drop-off becomes "Assertive."
Your argumentative boy that makes you actually use the phrase "Because I said so!" (because no amount of rationale makes a dent on him) becomes "Opinionated or Strongly Committed to One's Goals."
See! It's all how you look at it. :) If you can keep a positive attitude and astral project yourself into the time and space of twenty years in the future, you will see that these children that drive you to the brink of madness and court-ordered anger management will be amazing, functional, successful adults.
And way more interesting than those easy (boring), agreeable (sycophantic), obedient (sheep-like) children that you feverishly wish your children would be at least some of the time.
Look at the personality just ooze off these little whippersnappers! Future presidents of commerce and industry, I am sure of it. :) (And a proud Grandma, to boot.)