My father is nicer to his grandchildren than he ever was to me

Dear Delyara, My father was strict when I was young. Not just rules—shouting, insults, punishment for small mistakes, affection given mostly when I achieved something. With my children, he is gentle. He kneels to tie shoes, laughs when they spill juice, tells my daughter she is perfect after she loses a race. Everyone says becoming a grandfather changed him. Yesterday, I watched him comfort my son after a bad report card. Dad said, “A mark doesn’t tell me who you are.” I had to leave the room. When I brought home a poor report at twelve, he tore it in half and called me lazy. I am glad my children get this version of him. I am also furious that the tenderness existed somewhere inside him all along and apparently became available after I was grown enough not to need it. He once asked why I seem tense when he plays with the children. I said nothing. How do you tell your father that watching him become the man you needed is both beautiful and one of the cruelest things he has ever done?