Complex sentence: She insists that the stepmother harasses Su-Yeong, locking her in the closet, her father informs her that Su-Yeong is dead, and that she is not getting better.
Split into simpler sentences: She insists that the stepmother harasses Su-Yeon, locking her in the closet. Her father informs her that Su-Yeon is dead, and that she is not getting better.