There are some books I would add to her list. We love Night Tree by Eve Bunting. It is about a family who has the tradition of going into the woods every year to decorate a live tree with food for the animals in the forest.
Tomie dePaolo's The Legend of the Poinsettia and The Birds of Bethlehem are some of our favorites. The Legend of the Poinsettia is about a girl's unselfish gift to baby Jesus. The Birds of Bethelehem is the nativity story from birds perspective. It is beautiful!
The Year of the Perfect Christmas Tree by Gloria Houston is another touching and inspiring story. Ruthie's family provides the town they live in with a Christmas tree each year. With Ruthie's father off to war it falls to Ruthie and her Mom to get the tree and continue the tradition.