Didn't understand a comment Roman made in final episode
Toward the end of the episode when Shiv held back her deciding vote, Shiv, Kendall, and Roman argued in one of their offices. Roman made an insulting comment to Kendall about bloodline. He said, "One is a buy-in, and the other is half Rava and half filing cabinet installer." Kendall then flips out and squeezes Roman's face (I think) where he was wounded in the previous episode.
Was Roman stating that Kendall was not the biological father of his two kids, and was the the first time we were being told of this? Or was this mentioned at some point in the past, but Roman was now abusing that knowledge to say it in the most hurtful way he could?
I don't remember learning about any questionable parentage with regard to Kendall's kids before this point.