Unreasonable: Your 6-month-old will sit quietly (or sleep) in her car seat for a three-hour drive.
Reasonable: She'll probably get cranky—especially if you're stuck in traffic. One of you may have to sit next to her and sing or find other ways to keep her entertained.
Unreasonable: Your 4-year-old will be adorable playing the role of the Itsy-Bitsy Spider in his preschool play.
Reasonable: While you're waiting with your video camera in the first row, he'll become hysterical and refuse to walk onto the stage.
Unreasonable: Your 2-year-old will be the cutest little flower girl in your sister's wedding—walking down the aisle and posing for photos like an angel.
Reasonable: She'll get overwhelmed by all the attention, need you to carry her down the aisle, pose in very few group photos, and will be out of her dress before dinner is served.
Unreasonable: Soon after you've finally ditched diapers during the day, your child will be able to sleep through the night wearing his undies.
Reasonable: Potty training usually comes in two parts: daytime and nighttime. It may be months—even years—before he's dry all night.
Unreasonable: Your 3-year-old will sit at the table for a family dinner and listen to the grown-up conversation.
Reasonable: She may only last 15 minutes. Give her a toy or a coloring book to keep her amused, or let her be excused from the table.
Unreasonable: If you say no to your 9-month-old when he's about to do something that's dangerous, he'll get startled and then stop immediately.
Reasonable: He'll stop, smile at you, and continue trying to chew on the lamp cord. You'll have to pick him up and move him.
Unreasonable: Your 18-month-old will hold your hand as you walk together through the mall.
Reasonable: She'll run off ahead to explore any chance she gets. Take your stroller.
Unreasonable: Your 4-year-old will sit patiently and watch his cousin open his birthday presents.
Reasonable: He'll freak out because he hasn't gotten any gifts, and he'll want to unwrap the birthday boy's for him.
Unreasonable: You'll be able to enjoy yourself at an adult holiday party with your 22-month-old (especially when the host has encouraged you to bring her).
Reasonable: If there's a staircase in the house, you'll spend the entire time walking up and down the steps behind your toddler. And you can just forget about eating.
Unreasonable: Your 6-year-old can answer the telephone and say, "I'll get Mommy."
Reasonable: Normally a motormouth, she's suddenly speechless after she picks up the phone and then decides to hang up.
Unreasonable: Your 3-year-old will always remember to say "please" and "thank you" —especially when she's with her grandparents.
Reasonable: You'll probably have to remind her a thousand times before she does it automatically (and then you'll still have to nudge her every now and then).
Unreasonable: Your potty-trained preschooler will be able to wipe himself after he poops.
Reasonable: He'll need you—or his teacher—to do it for him.
Originally published in the October 2007 issue of Parents magazine.