Penny Jameson is at the end of her tether with her noisy, unruly children, and not being able to feed her baby. Then a young girl called Vicky arrives. With her calming, authoritative voice, she manages to get the children to obey her, and feed the baby without mess. Her smiles makes Penny think all is well with the world, it makes the wallpaper blue, and Penny never hears her arrive or leave. Penny finds out the truth from her neighbour – she is her granddaughter, who is Heaven sent.