Rose Wilder Lane's sole heir draws on family papers, Lane's published works, stories she told, and historical research to extend her mother's fictionalized family history into the next generation. Rose was ten in 1894 when Laura and Almanzo left their failed South Dakota farm for Missouri. MacBride recounts their journey, with four horses but few other possessions, and their purchase of a farm with forested land almost too rocky to plow and saplings yet to be planted for an orchard. By winter, they encounter strange new animals, cope with financial hurdles, and discover friendly neighbors; the book concludes with a barn- raising. MacBride emulates Wilder's style with some success, dwelling on similar concerns (the comfortable balance between a child's good behavior and a lively independence of mind) and details (especially of the land itself, and of making a cozy home with very little), choosing incidents of intrinsic interest as well as period authenticity. His characterizations aren't as rich as Laura's; there's no docile sister as a foil for Rose, as Mary was for Laura. Interestingly, Laura herself is best realized here, courageous but not indefatigable, with more doubts than Ma ever revealed. The author's careful prose doesn't match Wilder's elegant, artless-seeming simplicity; omitting some of the less telling details and phrases would have tightened the long text. Still, a fine continuation of the beloved chronicle, in similar attractive format (including quietly evocative soft-pencil illustrations of places and things). First printing of 100,000. (Fiction. 7-12)