You are not missing anything. Not sure what happened in the past when Yujin's dad hunting him but surely now the dad want him to be gone. For him, Aaron is a sole reason why his wife got into car accident. And it seemed he take his sweet time executing his plan.
Ohhh, that's what it is.
So that means, Aaron when he talked about being chased by someone that looked like Yujin was the dad. So 1st attempt was failed, now he wants to get revenge by Yujin relation with Aaron...
Yup. Aaron already knew Yujin is his son.
Is yujin's dad talking about Aaron when he said "that star"? He trying to get revenge by killng aaron? Am i missing the point?