I was worried too when I had my little girl. I thought she'd end up being a little madam as she was the oldest and the only child for a few years.
I remember as a child, my parents always said that girls are harder but the most rewarding.
AND, when I had my son, it turns out he was harder to bring up than my daughter - go figure!
I think you'll be an awesome mom, congratulations and all the best, truly!
Elly