WHO WAS AMASA'S FATHER?  ITHRA OR JETHER?

II Samuel 17:25. And Absalom made Amasa captain of the host instead of Joab: which Amasa was a man's son, whose name was Ithra an Israelite, that went in to Abigail the daughter of Nahash, sister to Zeruiah Joab's mother. (KJV) I Chronicles 2:17. And Abigail bare Amasa: and the father of Amasa was Jether the Ishmeelite. (KJV)

Both Ithra and Jether are variations on the name "Jethro", so they're likely the same person.  Not a contradiction.