Complex sentence: Her parents were very supportive of their only child's love for reading and learning, which was so great that her mother forbade the servants from giving Elizabeth candles to read by at night, although that didn't stop her for long.
Split into simpler sentences: Her parents were very supportive of their only child's love or reading and learning. She love for reading was so great that her mother forbid the servants from giving Elizabeth candles to read by at night, although that didn't stop her for long.