Arrow was a brother to the economist Anita Summers, uncle to economist and former Treasury Secretary and Harvard President Larry Summers, and brother-in-law of the late economists Robert Summers and Paul Samuelson.
Arrow adalah abang dari ekonom Anita Summers, paman dari ekonom dan mantan Menteri Keuangan AS dan Presiden Universitas Harvard, Lawrence Summers, dan saudara ipar dari ekonom Robert Summers dan Paul Samuelson.