Grandfather Go is now in a fit of anger. For many years he had kept it to himself and never told the truth to Jeff about his mother's involvement with his fathers' death. Maybe now is the time. It's been long enough; even though he doesn't have any proof, in his guts, he knows she and her husband had something to do with the death of his son.
"If you don't want to lose both of your sons, you better stay as far away from my family and me. It's the last time I'm warning you. The next time I will not hesitate, you understand!"
Olivia knows better than to argue with the older man. What he's saying is the truth. Her now ex-husband was the one who put a hit on Alex Go, Jeff, and Ethan's dead father.
"Father-in-law, I'm sorry! I..."