K.M.
Welcome to KC! Once you get settled, you will love it here. There really is a lot more to do than most people think, and it's a great place to raise a family.
We use Cradle through College for our pediatrician. All of the doctors in that group are great and the staff is super nice. They are located at St. Joseph Health Center, which is at I-435 and Wornall. Maybe about a 15 minute drive for you from Belton.
I use Rockhill Women's Care for OB services. Again, all of the doctors are great. They also are at St. Joseph Health Center and they have an office in Lee's Summit.
Good luck and let us know if you need anything else!
K.