I'm a huge fan of Karen Kingsbury! She is by far my favorite author. You have to be careful with her books because you might start at the wrong series :). She has 3 different sets of series that go in order. You can find out which one to start with here.
I recently finished reading The Above the Lines series. I've waited several months for books 3 and 4 to come out. I purposely waited for book 4 to be released before reading book 3. I must say they were excellent. Unfortunately, the tale still isn't over. Karen is going to write another set of books to finish the story of Bailey and Cody. I'm a bit sad I have to wait until the month after Little Bump is born :(. But that's okay! That just means I'll have something to occupy my time during those late night feedings!