Complex sentence: Millie and Christine were born on July 11,1851 to parents who were slaves, on the plantation of Mr. Alexander McCoy, near the town of Whiteville, North Carolina; this birth location resulted in the girls also being referred to as the Carolina twins.
Split into simpler sentences: Millie and Christine were born on July 11,1851 to parents who were slaves, on the plantation of Mr. Alexander McCoy. The plantation was near the town of Whiteville, North Carolina, which resulted in the girls also being referred to as The Carolina Twins.