On his way back from Sleepy Eye, Isaiah Edwards meets up with a dying old man, whose last request is for Isaiah to take care of his three-year-old, Blanche. It isn't until later that Isaiah realises that this 'little girl' is actually an orang-utan. Most of Walnut Grove is happy to welcome Blanche into their community, but the trouble starts when Harriet Oleson gets involved. Elsewhere, Willie Oleson's parents are shocked when their son announces he is planning to get married