Watch: Jack Schlossberg Honors Late Sister Tatiana Schlossberg With Childhood PhotoJack Schlossberg is holding sister Tatiana Schlossberg's final words close to his heart. Months after Caroline Kennedy's youngest daughter died Dec. 30 following a battle with myeloid leukemia, the political commentator-who is running for congress-shared his sister's last words to him. "I can tell you now that she's still rooting for us," Jack told CBS News Sunday Morning Mar. 1 of his campaign efforts. "The last thing that she said to me was, 'You better win.