Sun Lang, remembered by history as the man who accidentally burned his own camp to the ground, is the only son of Sun Jian who was not born to Lady Wu. Instead, he was born to by another woman. The identity of his biological mother is somewhat unclear, but it is possible that she was a recognized, official concubine of Sun Jian. There is yet the possibility that it was a more casual acquaintance, but there is no concrete documentation of this.
He worked as a palace guard in Wu commandary for some time. Sun Lang, quite honestly, was far from being one of his father’s most impressive sons; he did command a unit at Dongkou, but with rather poor results. A fire attack was initially planned, but since the weather was poor, the plan was cancelled. However, Sun Lang disregarded this order and ended up accidentally burning his own camp as well as many of another officer’s ships. Wu was still somehow able to win the battle, but Sun Quan was understandably disgusted with his younger brother’s foolishness.
Sun Quan took drastic measures and imprisoned Sun Lang, denouncing his half-brother as a part of the family. He went so far as to change Sun Lang’s family name to Ding, making his name Ding Lang. Taking the prestigious Sun name away from him was one of the greatest disgraces that could be faced for his blunder.