According to the "Heike Monogatari," his last words at his execution are said to have been--'Has Uemon no kami (Kiyomune) already been executed as well?' showing his consideration for his son.
『平家物語』では処刑の直前、最期の言葉は「右衛門督（清宗）もすでにか」と我が子を思うものであった。