I Chronicles 25:22 Midrash

לַחֲמִשָּׁ֤ה עָשָׂר֙ לִֽירֵמ֔וֹת בָּנָ֥יו וְאֶחָ֖יו שְׁנֵ֥ים עָשָֽׂר׃

For the fifteenth to Jeremoth, his sons and his brethren, twelve;

Read midrashic interpretation of I Chronicles 25:22: and classical rabbinic exegesis.