four o'clock
And you know you have some cold , already . '' `` All right , '' sighed Billy . `` Then it 's me for the knitting work and the fire , I suppose , '' she finished , with a whimsicality that did not hide the wistful disappointment of her voice . She was not knitting , however , she was sewing with Aunt Hannah when at four o'clock Rosa brought in the card . Billy glanced at the name , then sprang to her feet with a glad little cry . `` It 's Mary Jane ! '' she exclaimed , as Rosa disappeared .