Sarah Simpson likes to get big ideas that will solve problems. But her best friend, Peter, presents her with a problem that seems impossible to solve. He wants a dog, but his granny Belle won't let him have one. She says a dog would be too much work. Sarah tries to convince Peter to get another pet. But nothing works . . . until a stray cat turns up. Will Peter accept it? Will Granny Belle come around? Finally Sarah comes up with just the right BIG IDEA to solve the problem!