Complex sentence: His problems worsen when Emily contracts polio, which Margaret believes to be divine retribution for their sins; she considers cleansing her soul by testifying against Nucky, which would almost certainly send him to the electric chair.
Split into simpler sentences: His problems worsen when Emily contracts polio, which Margaret believes to be divine retribution for their sins. She considers cleansing her soul by testifying against Nucky, which would almost certainly send him to the electric chair.