Long Jian didn't consider his youngest half-sister, Long Xiulan, as a threat. The one he wanted to overpower was the heir, Long Hui.
He heard from Long Xiaopeng's latest report that Long Hui was having a difficult time with the elders after leaving the ancestral residence to move in with his lover and his child. The elders thought that it was disgraceful. They were accusing him of disregarding his duty as heir of the Long family.
Their father's birthday would be coming in a few days. All of the Longs would be gathering together for a grand celebration in honour of Long Tengfei. Long Jian couldn't wait to witness with his own eyes how Long Hui was being suppressed by the elders and the other members of the Long family.
'Now he'll experience something similar to the oppression that I experienced just because I'm an illegitimate son. Let's see if he can handle it. The Crown Prince will soon fall,' he thought.