Eric's lover 4

Rong Rong has been close with Aunt Lin and thus Sun Bingwen too met her when he went to Chenguang's room to fetch her the previous time.

They had a few conversations during these past days too. After all, Aunt Lin was an assistant to Chenguang who was the female lead acting opposite Sun Bingwen. 

Even if they want to avoid each other, they can not avoid it completely in this workplace. Let alone, they are not trying to avoid each other but on the contrary, Sun Bingwen got to know that Chenguang and Gao Renshu were married and they got a little closer when they were in Ren weimin's villa.

Hence they had shared more time with each other compared to before and thus Sun Bingwen knows what type of a woman aunt Lin was.

There is definitely no way that such a sweet woman would give birth to a woman who would have an affair behind her husband's back