No one intended to leave Martha alone that afternoon, but it happened that everyone was called away, for one reason or another. Mrs. McFarland was attending the weekly card party held by the Women's Anti-Gambling League. Sister Nell's young man had called quite unexpectedly to take her for a long drive. Papa was at the office, as usual. It was Mary Ann's day out. As for Emeline, she certainly should have stayed in the house and looked after the little girl; but Emeline had a restless nature.
I have two question about the passage.
1. Sister Nell = a nun or an aunt or elderly sister of Martha?
2. what is young man? a husband, a brother, a servant?
Thank you Anglika