Boy did I goof. I know that Sarah Bush was Abe’s Step-Mother, and Nancy Hank was his birth mother. Hence, my post below is completely incorrect; although Abe did love his mother very much (and his step-mother) and I think I am going to read this book regardless. It is fairly small so although it smells like old books tend to, it should be a quick read. I apologize for my inaccurate information!
This book is about Mr. Lincoln and the relationship he had with his Step-Mother, whom he grew to love very dearly. He had a difficult time when his Mother passed away.
booksandopinions.com 
Cool! Where do I find this book??
I found this book on E-bay, and I actually did a search for it after seeing your post and I couldn’t locate one for sale at the moment. This book was also about his mother, not his step-mother. I explained in my post I edited about the huge goof I made! LOL
All I can say, is it was one of those days!