I tell a similar story for my grandfather, who lived pretty much the same years as your mother. When my grandfather was born, his father's business was a horse changing station for the Madrid-Bilbao stagecoach. Eventually my great-grandfather sent his older kid (my grandfather's brother) to France to study cars at Renault, so he could turn the business into an automobile repair shop and service station. In the 70s my grandfather would fly to the US on a Jumbo jet. From stagecoach to trasatlantic flight in one generation.

Heinlein's novel: I think you are talking of Door Into Summer. It also contained a precursor to the Roomba. It was called something like the Mechanical Maid, but the description is of a vacuum-cleaning creeper.