GREAT SECRET Whoever Katy was, and whatever she might have done, nobody in Pleasant Valley knew anything about her except Kiddie Katydid and his numerous and noisy family.To be sure, many of the wild folk--and the people in the farmhouse, too--remembered hearing her name mentioned the year before.But they had quite forgotten about her, until August came and Kiddie Katydid and his relations brought her to their minds once more.