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Meg was Amy's confidant and monitor, and, by some strange attraction of opposites, Jo was gentle Beth's. To Jo alone did the shy child tell her thoughts; and over her big, harum-scarum sister, Beth unconsciously exercised more influence than any one in the family. The two older girls were a great deal to one another, but each took one of the younger into her keeping, and watched over her in her own way; "playing mother" they called it, and put their sisters in the places of discarded dolls, with the maternal instinct of little women.