Calvin's gift was communication. He tries to pull Charles Wallace from IT using his words, and he did for a split second. Then IT claimed Charles Wallace again. Only at the very end does Charles Wallace get released, but if… Full Answer
Charles Wallace is Meg Murry's younger brother. He is a very intelligent kid! Later on in the book, IT manipulates him, and Meg saves Charles from IT. Read the book to find out HOW Meg saved Charles Wallace!