I'm not at all convinced that Zach truly is Brian's son. I have a sneaky suspicion that may simply be his cover, and that perhaps his actual goal is to get in tight so as to have free access to Brian's singing superstar wife (whose name I don't remember).

PS: Who's the guy at the end of last night's episode who doesn't look/seem at all like a P.I., but who retrieved Zach's water bottle (obviously intending to have it DNA tested) from the trash container? I didn't get the impression that man is someone Brian hired. Having said that, I had just minutes earlier, while watching the episode, wondered to myself: "Why isn't Brian asking Zach to be DNA tested?"

@genplant29 said:

Having said that, I had just minutes earlier, while watching the episode, wondered to myself: "Why isn't Brian asking Zach to be DNA tested?"

Getting a DNA test would be too easy. In real life that would be the first and easiest thing you'd do, but in the world of make-believe it's one of the last things. First there's a lot of drama and looking for other ways to find the truth.

One of the storylines of the TV show "The Blacklist (2013-)" was finding out if the protagonist, criminal mastermind Reddington, was the father of one of the FBI agents. The FBI had him in custody, but they didn't test his DNA. Finally in season 5 a very old shirt, which might have belonged to him, was tested. They got sort of an answer. Then bones in a bag were discovered and these were also tested, resulting in a different answer. At the end of season 6 the FBI agent was told by the grandfather who Reddington really was. In the coming season 7, we'll find out if that's the truth. And still, no direct DNA test.

I don't think that in this show it'll take that long before someone suggests that Brian should have a DNA test done. Unless he doesn't want to hurt his 'son's' feelings by doubting him or his mother's words. If he doesn't want to do the test, then I'm sure that more people will turn up claiming that they're his son or daughter.