Newbery Medalist MacLachlan offers a quietly moving Christmas story that illustrates the power of children to change their world. Lily, the first-person narrator, and her younger brother, Liam, spend every Christmas vacation at their grandparents’ farm. Liam wants to buy a cow as a companion for the family’s pet, White Cow, who seems lonely out in the field by herself. By Christmas Eve, Liam has raised enough money to buy a calf companion, but there is also a Christmas surprise of several cow visitors brought by neighbors to keep White Cow company for the holiday. MacLachlan uses her typical taciturn style featuring dialogue and minimal description to convey the intense feelings of the sensitive little boy trying to accomplish a seemingly impossible task. Floca’s delicate, full-page pencil illustrations complement the text with understated emotion. (Fiction. 7-10)