<P> Sandy and his twin brother Dennys are the middle children in the Murry family, older than Charles Wallace but younger than Meg . They are 10 years old at the time of this book . Sandy is named after his father, Dr. Alex Murry . Although they are certainly intelligent, Sandy and his twin are considered the "normal" children in the family: B students, good at sports, and well able to fit in with their peers . Of the twins, Sandy is generally the leader, and the more pragmatic of the two . He and Dennys first appear in Chapter One . </P> <P> Dennys is the twin of Sandy Murry . Dennys and his twin are usually inseparable, with Dennys generally following Sandy's lead . However, Dennys is slightly less skeptical than his brother about the strange theories and even stranger adventures of Meg and Charles Wallace . (Note: The name Dennys is a shortened version of "Dionysus", which is the name of a Greek god, but is pronounced the same way as the more common spelling "Dennis .") </P> <P> The wife of the constable in Meg's hometown, who has twelve bed - sheets stolen from her at the beginning of the novel . </P> <P> Mr. Jenkins is Meg's cold and unfeeling high - school principal who calls her "belligerent and uncooperative" and implies that her family is in denial about Mr. Murry's true whereabouts . </P>

Author's purpose of a wrinkle in time