Final answer:
Jacob sent his sons to Egypt to buy grain during a famine. They interacted with Joseph, who had become a powerful figure in Egypt after being sold into slavery by his siblings.
Step-by-step explanation:
Jacob sent his sons to Egypt to purchase grain during a famine. This event is chronicled in the book of Genesis in the Bible and is part of the story of Joseph, who was sold into slavery by his brothers and eventually rose to power in Egypt as Pharaoh's trusted advisor. When a severe famine struck the region, Egypt had stored grain because of Joseph's foresight, and thus Jacob's sons made several trips to Egypt to buy grain, ultimately leading to a family reunion.