3 major milestones in the life of a 4 month old

Forgot to mention...
1. The two bottom teeth still aren't out yet, but they will be soon!
2. I don't know what's going to happen first-rolling over from back to tummy or tummy to back. It will happen within the week, I think!
3. Aila smiles ALL the time, but she still hasn't giggled yet...she'll let out a little "heh-heh" sound every so often, but it's not really a giggle. It'll happen soon, though, too!