Lu Deyin was not in a hurry to avenge her parents. Having already waited for so many years, so what if she waited a little longer?
Since she had just married into the Qi family, not only did she have to get used to her husband, but she also had to build a good relationship with her mother-in-law. Since she knew that her younger brother was someplace safe, she wasn't in a hurry.
But even though she was not in a hurry, Eldest Master Lu was!
He was dying to know why his Fourth Brother was investigating him and how much he'd found out. He was anxious to get rid of the people who knew about this. He was also anxious to control Lu Jiashu and prevent Lu Deyin, who had married into a wealthy family, from escaping his control.
When one was anxious, mistakes were inevitable. Lu Deyin had only returned home for two days before a huge scandal broke out in the Lu family.
Eldest Master Lu failed to poison Fourth Master Lu, giving the latter a hold over him.