I Chronicles 25:11 Midrash

הָרְבִיעִי֙ לַיִּצְרִ֔י בָּנָ֥יו וְאֶחָ֖יו שְׁנֵ֥ים עָשָֽׂר׃

The fourth to Izri, his sons and his brethren, twelve;