'Oldest' in the Bible

The sons of Samuel: Joel the firstborn and Abijah the second oldest.

The sons of Ladan: Jehiel the oldest, Zetham, and Joel -- three in all.

Jahath was the oldest and Zizah the second oldest. Jeush and Beriah did not have many sons, so they were considered one family with one responsibility.

The son of Gershom: Shebuel the oldest.

The son of Eliezer was Rehabiah, the oldest. Eliezer had no other sons, but Rehabiah had many descendants.

The son of Izhar: Shelomith the oldest.

The sons of Hebron: Jeriah the oldest, Amariah the second, Jahaziel the third, and Jekameam the fourth.

The sons of Uzziel: Micah the oldest, and Isshiah the second.

Just like their relatives, the descendants of Aaron, they also cast lots before King David, Zadok, Ahimelech, the leaders of families, the priests, and the Levites. The families of the oldest son cast lots along with the those of the youngest.

They cast lots to determine their responsibilities -- oldest as well as youngest, teacher as well as student.