Midian's sons were Ephah, Epher, Hanoch, Abida, and Eldaah. All of these were Keturah's descendants.

Midian’s sons: Ephah, Epher, Hanoch, Abida, and Eldaah.
All of these were Keturah’s sons.

I am dark, but lovely, you daughters of Jerusalem, like Kedar's tents, like Solomon's curtains.

All Kedar's flocks will be gathered to you, the rams of Nebaioth will serve you. and they'll come up with acceptance upon my altar, and I'll glorify my glorious house."

Of Kedar. And of the kingdoms of Hazor Which Nebuchadrezzar king of Babylon smote - Thus, saith Yahweh, - Arise ye go up against Kedar, So shall they spoil the sons of the East: