The land will mourn, each clan by itself, with their wives by themselves: the clan of the house of David and their wives, the clan of the house of Nathan and their wives (NIV)
And the land shall mourn, every family apart: the [kingly] family of the house of David apart and their wives apart; the family of the house of Nathan [David's son] apart and their wives apart (AMP)
And the land shall mourn, every family apart; the family of the house of David apart, and their wives apart; the family of the house of Nathan apart, and their wives apart; (KJV)