As of my last knowledge update in April 2023, Andrew Child is an English novelist best known for his thrillers. Born in 1968, his real name is Andrew Grant, and he is the younger brother of Lee Child, the creator of the Jack Reacher series. Andrew Child has had a successful writing career in his own right, penning a series of novels featuring the protagonist David Trevellyan. In recent years, he has collaborated with his brother Lee Child to co-author installments of the Jack Reacher series, starting with the book "The Sentinel," which was published in 2020. Andrew Child's work is characterized by fast-paced action, intricate plotting, and strong, engaging protagonists.