My daughters hair is very similar. I have 3b and she has 2a (used to be 2c until it got below her waist and then baby hair was cut away and they never came back).
We have to make sure a heavy conditioner is used with a wide tooth comb when she gets a bath and then braid (since it's gotten thicker, it falls out less).
Between washes a friend gave us a brush that has both hard and soft bristles and it seems to work.
I just recently started using Shea Moisture on all three of us (son has 3a) and it seems to be working at keeping hers from getting too dry. If she has a bad morning, I use a Garnier Triple Nutrition Spray to get it going.
I hate leaving her hair loose because by the time she gets home from school it's matted in places and she doesn't want it cut again because GeeGee (my mom) cut it too short last time (according to her but not us).