Karen's Promise (The Baby-Sitters Club Little Sister, No.95)

Karen promised her brother Andrew that they'd never be separated. When Karen's mom and stepdad announce they'll be moving to Chicago for six months -- with Andrew -- Karen's promise is put to the test. When Karen and Andrew's mother and stepfather plan to move to Chicago for an extended period, they decide to take Andrew with them, but let Karen decide whether to go or to stay with her father in Connecticut. Karen's decision is complicated by her promise to Andrew that they would stay together, no matter what