The best part of parenting is getting to know the persons you have brought into the world. They have clear personalities from the minute they are born, and it is really fun trying to lure out the good sides, and less fun teaching them to subdue the less socially acceptable sides of their personality.
I'm an very clear introvert, but 90 % of those that don't know me think I'm an extrovert. Speaking for crowds is no problem, small talk in the lunch break at work is enjoyable, etc. But after a day at work I need a couple of hours alone. If I need to consentrate the office door will be closed, and I never take part in office parties or other social settings where you are supposed to be around people "for fun". My husband is my only real friend, and the moment I realized that one friend was all I wanted or needed, life got much easier. My parents tried to get me to be an extrovert, and it was hell. They would invite 15 girls to celebrate my birthday, and I would hide in the attic with a book.
The youngest kid is just like me. She loves singing in front of large crowds, but has to have at least one day a week where she is completely alone: sitting in her room drawing, taking a walk alone, etc. As a baby, we had a lot of trouble getting her to sleep, until we discovered she hated to be cuddled to sleep. Put her in the middle of a queen sized bed, leave the room, and she was asleep within a few seconds. The oldest kid, on the other hand, needs to be around other people constantly. When she can't be in the middle of large groups, she will put on some sort of sound (tv, radio, audiobooks, etc) in the background to avoid feeling lonely. As a baby, she would rather sleep in the middle of the living room than alone in her room.