Kate Klise and illustrator M. Sarah Klise are sisters who have been writing each other letters for more than twenty years, culminating in 1998 with their fiction debut, Regarding the Fountain. When they're not writing letters, Kate who lives in Norwood, MO, is a correspondent for People; Sarah is an art teacher that lives in Berkeley, California.

As a correspondent for People magazine, Kate Klise covered everything from celebrity scandals to serial killers. After writing several bestselling children's books, Kate decided to write In the Bag, her first novel for adults, when she found a note from a fellow passenger in her carry-on bag.