It is interesting that Lucy and Joseph Smith, Sr. named their first son Alvin, their second son Hyrum, and only then named their third son Joseph Smith, Jr., after his father. That is not how it usually worked in the 1800s. If there was going to be a Junior, he was usually the firstborn son. But Alvin was not the great seer of whom Joseph in Egypt and Lehi had prophesied. It was Joseph Smith, Jr., the thirdborn son. Somehow, the Lord inspired his parents to name their children in that order.
Joseph Smith, Sr. was the first to hold the office of patriarch in this dispensation. He was the oldest man of the blood of Joseph, meaning that he was the oldest direct lineal descendant of Joseph of Egypt on the earth at the time. Brigham Young said that the Lord watched over the blood from Ephraim down through the generations until it came to Joseph Smith, Sr. and Lucy Mack Smith and that Joseph Smith was a pure Ephraimite.
Whatever that may mean, Joseph Smith Jr. also had the blood of Joseph, the blood of Israel, the blessings of Abraham, Isaac and Jacob, flowing in his veins, and he was the great seer that has been prophesied by his ancestor Joseph who was sold into Egypt.