Eleven-year-old Miri Gill feels left out in her family, which has two sets of twins and her, until she travels back in time to 1935 and discovers Molly, her own lost twin, and brings her back to the present day.
When Bean's parents leave her in the care of her older sister Nancy for the afternoon, she enlists her neighbor and best friend Ivy to come over and teach Nancy how to be a really good babysitter.