Mia is showing off her teeth! All four of those top teeth came in at the same time! You would've expected her to be unbearable, but she was actually not too bad. I can't even imagine how much that must hurt. I'm glad it happens at an age we can't remember it.
If you're wondering when your baby's teeth may come in here's a chart though keep in mind that all children are different. Mia didn't get her first two teeth until she was 11 months old...and since then it's been going pretty fast. Some babies may get their teeth earlier too. I know someone who's baby was born with 2 teeth already!