During Former Qin
Fu Jiān made most Former Yan princes commandery governors in his empire, and both Murong De and his brother Murong Na were commissioned as such, but Murong Na was soon removed from his office, and both Murong Na and their mother Consort Gongsun relocated to Murong De's post at Zhangye Commandery (張掖, roughly modern Zhangye, Gansu). Around or in 383, when Fu Jiān prepared a campaign to destroy Jin and unite China, Murong De and his troops were mobilized, and he left his own sons, Murong Na, and Consort Gongsun in Zhangye; before leaving, he gave his mother a golden knife as a sign of his devotion.
After Fu Jiān's defeat by Jin forces at the Battle of Fei River, Murong De first tried to persuade Murong Chui, to whose camp Fu Jiān had fled, to kill Fu Jiān and start a rebellion to rebuild Yan. When Murong Chui refused, citing Fu Jiān's kindness to him, Murong De then tried to persuade Murong Wei to do so, but Murong Wei also refused.
In spring 384, however, Murong Chui did start a rebellion near Luoyang, and after he claimed the title of Prince of Yan, thus establishing Later Yan, he created Murong De his old title of Prince of Fanyang. When the news reached Zhangye, the commandery governor Fu Chang (苻昌) arrested and executed Murong Na and all of Murong De's sons (and presumably their mother(s)). Consort Gongsun was spared because of her old age, while Murong Na's wife Lady Duan, who was then pregnant, was imprisoned to await for execution after she gave birth. Consort Gongsun and Lady Duan, however, were rescued by Murong De's former subordinate Huyan Ping (呼延平), who escorted them to the Qiang tribes.
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