Chu Qiao, a special agent, tells how Chu Qiao's brother died.

Brother Wu of Chu Qiao, I'm sorry. Taking advantage of the brocade candle, he gave a pair of poisonous money to Yu's grandfather. Both Linxi and his father were poisoned. At that time, I didn't know that there was only one kind of resurrection pill. After giving medicine to his grandfather, he realized that there was no other medicine. If there is no antidote, he will be very painful. Linxi asked Yu to kill himself to avoid that terrible pain, so Yu helped him.

I hope it helps you.