Jemuel is the son of Simeon (son of Jacob).
Genesis 46:10The sons of Levi: Gershon, Kohath, and Merari.
Exodus 6:15These are the names of the sons of Levi according to their generations: Gershon, and Kohath, and Merari; and the years of the life of Levi were one hundred thirty-seven years.