Princess Thiên Ninh Trần Ngọc Tha

Princess Ngọc Tha, titled Princess Thiên Ninh, was a daughter of Emperor Trần Minh Tông and Empress Hiến Từ and a sister of Emperor Trần Dụ Tông. She received the title in 1342 and married Trần Kham.

After Dương Nhật Lễ took the throne, he killed her mother. In 1370 her two sons joined a failed attempt by Trần kinsmen to kill Nhật Lễ and were killed; the following month she met her half-brother Trần Phủ and urged him to raise an army against Nhật Lễ. She helped bring about his fall and her brother's accession as Trần Nghệ Tông.