Zhu Wenkui

Zhu Wenkui was the elder son and Crown Prince of the Jianwen Emperor of the Ming dynasty, born by Empress Ma, when his parents were Crown Prince and Crown Princess respectively.
In 1402, Zhu Di, Prince of Yan sacked Nanjing, both Jianwen and Wenkui disappeared. It was said that Wenkui died in the palace fire set by Jianwen; or Wenkui was demoted to commoner rank and put under house arrest at Fengyang; when he was released, he was 61 and his son was about 40.
In the period of the Southern Ming, he was posthumously honored Crown Prince Gongmin and Crown Prince Hejian.
He was the only male royalty in Ming dynasty that born during the reign of his great-grandfather, and thus Hongwu Emperor was the only Ming emperor that lived to see his great-grandson born.