Jenny is a city child. On the third floor of a brownstone in Brooklyn Heights, she has dolls, books and records. But no pets. Jenny wants a dog. Mrs. Chalmers on the second floor squelched the idea of a dog --but suggested a cat. But Miss Bither, the first floor tenant, vetoed that idea. After all she had her petunias to think of. When they finished saying no, no, no, Jenny saw the horse. So she asked him in. Up to the third floor she marched him and into the living room, where he ate the ivy. Then down again, past Mrs. Chalmers and Miss Bithers --who learned their lesson. For shortly there-after, each came puffing upstairs, the former with a puppy, the latter with a kitten.