Picture Books:

Little Acts of Grace by Rosemary Gortler

Stories:

St. Therese and the Roses by Helen Walker Homan

Further Reading:

David and Goliath: Underdogs, Misfits and the Art of Battling Giants by Malcolm Gladwell

The Story of a Soul by St. Thérèse of Lisieux

The Tipping Point: How Little Things Can Make a Big Difference by Malcolm Gladwell